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Leonardo, Vol. 13, pp
11-16 Pergamon
Press 1980. Printed in Great Britain |
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Helen Thomas |
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Application of the Ostwald Color System in my painting |
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I. I
have often pointed out to my private students and to my artist colleagues
that one should not label certain colors 'muddy' when they are on a palette
or on a canvas. A color will seem 'muddy' only because it is seen in an
inappropriate context. I, therefore, was delighted to read in M. E.
Chevreul's book Eugène Delacroix's words: 'Give me mud and I will make the
skin of a Venus if you will allow me to surround it as I wish' [1, p. 33]. In
reflecting over Western painting since the turn of the century, particularly
with reference to the use of color, I feel that Abstract Expressionism left
an unfortunate legacy: a rather limited palette resulting from an
unpremeditated selection of color. But color awareness and sensitivity in
painting can be expanded through practice. Joseph Albers discusses this in
depth in his book, Interaction of Color
[2]. Contrary to his opinion, however, I feel that a color classification
system should be studied and applied in conjunction with an artist's own
experiments. I
have not been exclusively a colorist. When I attended The Philadelphia
College of Art, an early emphasis was placed on drawing technique and on a
knowledge of the human anatomy, a type of training that I endorse heartily. I
drew for two years, in a course consisting of six hours per day and four days
per week. On the fifth day I was introduced to allied areas; then color was
explained but superficially. My
art education continued at the Art Students' League in New York City. It was
there while studying under Sidney Gross that I changed from representational
painting to the style of Abstract Expressionism. The use of a quick drying
mixture of a medium with oil paint enabled me to work swiftly and to employ
color impulsively. This manner of painting was exhilarating for me, but I
felt the need to exercise more control in employing color. Nevertheless, in
Gross's class I did come to realize that |
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the color
of a layer of paint can be different in different surroundings. The color of
paint on my palette was often different after it was applied on canvas. And,
when Gross lectured on simultaneous contrast, using the color plates from
Albers' book, I learned the reason. Later I found that the elucidation of the
phenomenon was one of the many contributions to the knowledge of color made
by Chevreul [1]. In
1967 Gross left the Art Students' League teaching staff and Ben Cunningham
took his place. From the first class meeting, I heard Cunningham stress that
there were no rigid rules on the use of colors in painting. I learned, in
particular, about the extensive work in color done in Germany during the
early years of this Century by Wilhelm Ostwald, Nobel Prize Laureate in
chemistry, work aptly typefied by his words Harmonie and Ordnung
(harmony and order). This was my introduction to the Ostwald color solid, and color soon became the major aspect in my
painting. II. Ostwald
introduced a 3-dimensional classification System for surface colors [3]. This
System is given by a geometrical array of points in 3-dimensional
coordinates, each point representing a different color. The spatial array has
the form of a double cone and is
what is meant by the term Ostwald color solid. The double cone consists of
two identical cones having a common circular base, whose perimeter is the
equator; it is oriented so that one apex (the north pole) points upwards and
the other (the south pole) points downward. The
Color Harmony Manual of Jacobson,
Granville and Foss [4], which is well known, contains a set of color samples
whose selection was based on Ostwald's system and which are assigned
locations in the color solid. The color white is assigned the Position at the
north pole and the color black at the south pole. Twenty-four colors of
different hues and high purity are assigned to evenly spaced points on the
equator, and they follow in clockwise order the |
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sequence
found in the color spectrum (violet, blue, ... red). The circle is completed
with the inclusion of colors of nonspectral hues (reds and purples). The
precise hues have been selected so that each is opposed on the equator by its
complementary. This is one important feature of the set of samples in the Color Harmony Manual [5, 6]. If
one divides the double cone into two naives by a vertical plane passing from
the north pole to the south pole along the vertical axis and through two
opposite points on the equator to which complementary colors are assigned,
one exposes a diamond-shaped cross section like that shown in Fig. 1 (left).
The notations shown are those of Ostwald [3, pp. 36-39]; they are employed in
the Color Harmony Manual. Here a
designates white at the north pole and p designates black at the south pole.
Six neutral grays (c, e, g, i, l, n),
with increasing amounts of black and decreasing amounts of white, are
assigned to six equally spaced intermediate points. The vertical axis of the
double cone passing from a to p is called the gray axis (dashed line). The
gray axis divides the cross section shown in Fig. 1 (left) into two identical
triangles. The array of points defines 24 such triangles in the color solid.
All the colors (except white, black and the neutral grays) assigned to points
in a triangle have the same hue. In each triangle the color of maximum purity
is designated by pa shown at an
apex (Fig. 1, left). While it is important to remember that the double cone
is a geometric solid, it is helpful to imagine it as a form consisting of 24
equally spaced triangular vanes joined to the vertical gray axis. The model
made by the Ostwald laboratory, illustrated in Ref. 3, p. 35, shows the vane
structure. Fig. 1 (left) shows two opposing triangles joined on the vertical
axis, representing one set of two complementary colors joined by the neutral
grays. The fact that the colors represented by points in one triangle possess
the same hue is the second salient feature. Points
along the upper side of a triangle connecting the points for white and the pa-color represent mixtures of the two
colors. Similarly, points on the lower side represent mixtures of black and
the pa-color. Along either side,
the closer a point is to the |
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pa-color location, the higher is the
purity of the color represented. Points
within a triangle represent mixtures of white, black and the pa-color Fig. 1 (left). Vertical lines
passed through points represent series of colors in which both the purity and
the hue are held constant but in which the white content increases and the
black content decreases in progressing upward from one point to the next.
Such a series is called a shadow series,
which is of use to painters, for example in depicting shading seen on curved
uniformly colored surfaces. The constancy of both hue and purity in the
shadow series is the third significant feature. III. Ostwald's
choice of hues relates to Ewald Hering's theoretical interpretation of color
vision in which Opponent colors play a role: red and green, yellow and blue,
white and black [7; 8, p. 831]. The hues of the particular red, green, yellow
and blue are considered by Hering as unique in that, unlike any other hues,
each of them is perceived to have no admixture of another hue [3, pp. 3, 9],
These four hues are sometimes called the unitary
hues [8, p. 864]. Thus, unitary red has no perceived yellow-ness or
blueness. All other reds, however, possess either yellowness or blueness. The
Ostwald hue circle, corresponding
to the 24 colors of high purity, the pa-colors
(numbered from 1 to 24) on the equator, is based on the assignment of the
unique hues yellow, red, blue and green (sea green) to positions spaced at
90° on a circle, at numbers 2, 8, 14 and 20, respectively [3, p. 20]. At
intermediate points 5, 11, 17 and 23 are located the intermediate hues:
orange, purple, turquoise and yellow green (leaf green), respectively. The
hue circle is completed by adding one in-between hue to a position on each
side of each of the eight aforementioned hues. Thus, orange hue at 5,
possessing equal redness and yellowness, has as neighbors an orange with more
yellowness at 4 and an orange with more redness at 6. Although the spacing on
the equator is uniform, precise equality |
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in the
color differences has been sacrificed to permit the opposing arrangement of
complementary hues [3, p. 194]. IV. My
first assignment in Cunningham's class was to prepare a color wheel showing
the 24 colors of high purity (Fig. 2). As an aid, I referred to a copy of the
Color Harmony Manual [4]. The
artists' oil paints that I employed to represent the 24 colors (identified by
number in Fig. 2) were: (1) Rembrandt Lemon |
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Yellow;
(2) Rembrandt Medium Yellow; (3) and (4) mixtures of Rembrandt Medium Yellow
and Orange; (5) Rembrandt Orange; (6) mixture of Windsor Newton Cadmium
Scarlet and Rembrandt Orange; (7) Shivastra Red Light or Windsor Newton
Permanent Rose added to Windsor Newton Cadmium Scarlet; (8) Shivastra Red
Light or Windsor Newton Permanent Rose; (9) Rembrandt Talens Rose; (10) and
(11) mixtures of Rembrandt Talens Rose and Shiva Violet Deep; (l 2) Shiva
Violet Deep. The list continues for the blues and greens, Nos. 13 and 24, all
with the addition of Weber's Permalba white to raise the lightness, making
these colors more compatible with the others (but not an excessive addition
of white that would produce tints); (13) Windsor Newton French Ultramarine;
(14) mixture of Windsor Newton French Ultramarine and Rembrandt Blue; (15)
Rembrandt Blue; (16), (17) and (18) mixtures of Rembrandt Green and Rembrandt
Blue; (19) Rembrandt Green; (20), (21), (22), (23) and (24) mixtures of
Rembrandt Green and Rembrandt Lemon Yellow. To produce the neutral grays and
black, I added burnt umber to the black paint. After
painting the color wheel, my next project in Cunningham's class was to make
four charts of the type shown in Fig. 3, using the four following pairs of
complementary hues: red, green (sea green) (8,20); orange, turquoise (5,17);
yellow, blue (2,14) and purple, yellow green (leaf green) (11, 23). Each
chart shows five colors on the vertical axis (white, black and four neutral
grays), whereas in the |
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Ostwald
chart (Color Harmony Manual (Fig.
1)) eight (six neutral grays) are included. The eight hues are the four
unique hues and the four corresponding intermediate hues. The four charts and
the color wheel would suffice for reference purposes in my painting. In
the Color Harmony Manual, color
samples of a specific hue are presented separately in a triangular array as
shown in Fig. 1 (left). A presentation such as that shown in Fig. 1 (right),
however, would produce pleasing simultaneous contrast effects at the
boundaries of the samples. I employ presentations of this latter type but
with fewer colors (Fig. 3). My four charts of eight triangles contain 85 |
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different
colors, including white, black and three neutral grays; in the Manual, the 24 triangles contain 680 different
colors, including white, black and six neutral grays. I consider that my
charts representing 85 points in a double cone constitute a representative
sampling of the color gamut de-scribed by the Ostwald color solid and by the Manual, since I mixed those colors
common to my chart and Ostwald's (for example, ha (Fig. 3), which is between colors ia and ga in the Manual. The
three paint mixtures of colors between white and a pa-color were made
directly by adding Weber's Permalba white paint to the paint selected for the
pa-color. The colors of the series
from a to pa progressed in what I judged to be approximately equal perceptual
steps. The procedure was repeated for producing colors between black and the pa-colors. I employed Windsor Newton
Mars Black to which burnt umber had been added. The addition of burnt umber
was necessary to produce a neutral black. The three neutral grays were
prepared by mixtures of white with this black. The remaining colors of my
charts were the three in each triangle produced by mixtures of paints of
white, black and pa-color. To
prepare each mixture, the tint (the top mixture in the shadow series (Fig.
3)) was combined with the tone (the bottom mixture). In mixing, the tone was
added to the tint, as the reverse procedure often leads to the preparation of
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paint than
is intended. As a final check, I examined the colors in each triangle to be
sure that the members of each diagonal, vertical and horizontal series
differed progressively in a uniform way. V. After
attending Cunningham's class for one year, I became the monitor of the class,
a position that I held for three years. In this period I profited from the
experience of explaining the Ostwald concepts and of applying them both in
the preparation of displays for still life painting and in my own painting. The
experience gained in systematically preparing the color charts eliminated the
trial-and-error approach that I had previously used in preparing colors. I
learned that ochre and raw umber are, in effect, combinations of yellow and
black and that they belong to a triangle assigned to a yellow hue. But, as
indicated above, the black paints available to me possessed too much blue to
serve in the preparation of neutral grays from mixtures with white; I had to
add burnt umber to prepare a neutral black. The unaltered black paints mixed
with yellow paint produce greenish colors; so, in preparing yellows, I
employed white, pa-yellow and burnt
umber. For the orange reds I used burnt sienna. The use of burnt umber and
burnt sienna for darkening was limited to the colors 1-6 in the color circle
(Fig. 2). In
this period in Cunningham's class my paintings underwent a decided change. I
began to use flat planes in the depiction of disparate shapes in harmonious
colors. Later I introduced the illusion of transparency, and, with the aid of
perspective lines, I added depth and volume. In 1971 I began working with
elliptical shapes. The following is a description of a number of problems
that I met and solved. VI. In
1972 I exhibited a series of paintings entitled ‘Perpetual Motion'. Each
canvas displayed a number of overlapping ellipses presented either
horizon-tally, diagonally or vertically (Fig. 4). My intent in each was to
depict a segment of space of an unvaried scene suggesting uniform unending
motion and also to present an Illusion of transparency and volume. In
the ‘Perpetual Motion' paintings I required a background color and two
different uninterrupted sequences of color for use in the overlapping
ellipses. In the case of one painting, 'Perpetual Motion, F-3' for example,
the two series of colors were applied to show two parallel progressive color
changes across the surface of the painting and to give a feeling of depth
through a three-step progressive relationship from background to fore-ground.
In this particular painting I employed 32 colors: the background, one
progression of 16 colors of low purity (significant white and black content)
and one of 15 colors of high purity. |
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VII. In
my next group of paintings, the 'Partial Eclipse' series begun in 1974, I
planned the com-position differently (Fig. 5). After many trials I |
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arrived at
an arrangement of four overlapping ellipses that would serve as a basis for a
series in which the colors are planned so that there is a feeling of a
progression from the background to the foreground or vice versa [9]. By a
careful use of three or more colors in a progressive relationship I am able
to produce an illusion of transparency. I pay particular attention to value,
keeping the light/dark |
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contrasts
constant in order to preserve the identity of the geometrical form in the
series (Fig. 5). When
I plan a painting using the ‘Partial Eclipse' motif, I decide, first of all,
the mood of the picture. I then determine which group of nine colors in the
Ostwald color solid would best serve my purpose. I select the background
color 0 (Fig. 6) and the color |
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2B
for the center of the depicted form. Colors 0 and 2B need not be of the same
hue, but the hue variations are not large. I intend all the color changes to
occur in a progression between 0 and 2B, and I remember Cunningham's opinion,
'What a color does to the background it does to each color it touches.' To
produce subtle ethereal effects, I work with light near-gray colors of
slightly varying hues. To produce more contrast, differences in value and in purity
are increased. The
colors are selected as an ensemble to ensure that they will be in harmony. I
employ opaque paints to produce the illusion of transparency; I do not apply
transparent paint of one color over another. I emphasize the central form through
the use of its coloring and that of the surrounding areas. Interesting and
different results are obtained by reversing the colors—by the use of color 2B
for the background and color 0 for the center of the" depicted form or B
for the background and 2 for the center of the depicted form (Fig. 6). Although
I employ opaque paints of nine different colors in making a 'Partial Eclipse'
painting, the colors seem as though they were produced by superimposing
colored plastic films of two hues on the background. Each of the films
appears to be superimposed on the background in two of the four elliptical
shapes. One film seems to change the background 0 to a color A (Fig. 6). A
second film of the same hue applied to 0 appears to change it to color B
where A overlays A. In effect, in my choice of opaque colors the background
color is to be shifted two perceptually equivalent steps and the same two
steps are identified as colors A and B to establish a new parallelogram with
0, A and B composing one side (Fig. 6). I complete the other side of the
parallelogram, 0, 1, 2, using the same procedure by starting from the
background color |
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and
imagining a superimposed plastic film of the second hue. The remaining colors
are established by imagining further overlays of films. For example 2B would be produced by four overlays
on 0 (that is, two of A and two of 1). Similarly, 1 A
would be produced from 0 by one
overlay of A and one of 1; 2 A from 0 by one overlay of A
and two of 1; 1 B from 0 by one
overlay of 1 and two of A. VIII. Preparing
a satisfactory parallelogram of colors requires considerable testing and
altering of paint mixtures before the colors vary uniformly in the
horizontal, vertical and diagonal directions. The mixed oil paints are then
wrapped in plastic for storage. But before painting on canvas, I make a
preliminary sketch on a canvas board (20 x 25cm), which I eventually file as
a record of the work. The sketch, however, is not conclusive; on enlargement
on the canvas I may not find the areas of color aesthetically pleasing to me. Although
I have color preferences, I do not allow personal taste to interfere with my
color selection, believing that, if I did, my exploration of and experience
with color would be unnecessarily limited. I deliberately select colors in
regions of the color solid with which I have not previously worked, and I
seek color relationships that I have not previously employed. As a
consequence, I have produced unusual and to me very pleasing color combinations.
Often I select colors from a diagonal plane passed through the Ostwald color
solid from a light shade of one hue in one triangle to a darker shade of a
different hue several triangles away. These hues appear at different
lightness levels, helping to increase contrast: The
preparatory work in planning a picture is the crucial part. The task of
painting, though not difficult, requires precision. The templates for the
ellipses are cut from heavy kraft paper. Then I apply at least two thin,
smooth coats of paint of the nine colors before deciding finally whether the
sizes of the colored areas and the values and the purities of the colors are
acceptable. Minor adjustments in color can be made at this stage. I strive to
prepare a smooth surface, because surface variations tend to catch light and,
thereby, detract from the illusion of transparency. Since
artists' oil paints of different pigment type vary widely in oil content, I
used a matte varnish in the medium to obtain a smooth uniformly dull surface.
For the final coat I paint alternate areas, and, then, after the paint is
dry, I apply masking tape (6 mm) on those areas precisely to their edges, so
that the adjoining remaining areas can be completed without any breaks in the
surface. IX. The
illusion that I wish to produce in the ‘Partial Eclipse' paintings is that of
transparent discs slowly revolving in space, with a translational motion |
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forward or
backward depending upon the color composition. Many interesting variations of
the illusion are possible depending on which corner color of the
parallelogram (Fig. 6) is to serve as the background and to which ellipses
the remaining colors are assigned. Through an interest in these possibilities
I was led to make a series entitled 'Multiple Images' (Fig. 7 cf. color
plate). For these my canvas is subdivided by a 3 x 3 grid to accommodate nine
'Partial Eclipses' of identical shapes but with different assignments of the
same nine colors to the various areas [9]. To
establish the nine colors of the parallelogram, I selected a plane passing
through the color solid. I then constructed mentally a square or a rectangle
that enclosed a group of nine colors on the plane. These colors were then
painted in my chart (Fig. 6). In such work the colors that I paint in my
chart need not match the color chips of the Color Harmony Manual precisely, but they should differ
progressively in approximately perceptually equal steps. The
corner positions of the 3x3 grid are occupied by 'Partial Eclipses' that are
similar in coloring but smaller in dimensions than the individual paintings
in my 'Partial Eclipse' series (Fig. 7, cf. color plate). In each of these
four positions the background color corresponds to one of the four corner colors
(0, B, 2B or 2) of the
parallelogram (Fig. 6). For the 'Partial Eclipses', on the four side
positions of the grid, the color of the background is specified by either A, 1 B, 2A or 1. The color of the background for the central 'Partial Eclipse'
is given by 1 A. In
the painting 'Partial Eclipse', described in Section VII, I employed a scheme
of colors that depicts four transparent elliptical films of which two are of
one color and two are of another color. These I used in the four corner
rectangles of 'Multiple Images' (Fig.7, cf. color plate). The central rectangle
in this 3x3 grid depicts four elliptical films, each of a different color,
and the remaining four rectangles depict four films, two of which are of the
same color. The
'Multiple Image' paintings, I find, give the |
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feeling of
the release of a large amount of energy. I had prepared a triptych of three
such paintings for an exhibition of examples of my work, but I found that it
was so overpowering in comparison with single members of the ‘Partial
Eclipse' series that I decided not to exhibit it as a triptych. The three
parts, however, were exhibited as individual paintings. Although
I use ellipses almost exclusively, I do not consider myself a geometric
abstractionist. Nor do I consider myself a follower of the hard-edge style.
It is true that the edges are precisely painted, but the same effect could
have been obtained if the edges were irregular, as long as the juxtaposed
colors produced simultaneous contrast. But, if I had not taken advantage of
simultaneous contrast and of contrast between light and dark, I would not
have been able to produce the illusion of transparency. I wish to add,
however, that while I have applied my knowledge of color to a particular
style of painting, it can be applied to other styles. |
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REFERENCES 1. M.E. Chevreul, The Principles of Harmony and Contrast of Colors and Their
Applications to the Arts (1854): Introduction and explanatory notes by F.
Birren. (New York: Reinhold, 1967). 2. J, Albers, Interaction of Color (New Haven, Conn.: Yale Univ. Press, 1963). 3. E. Jacobson, Basic Color: An Interpretation of the Ostwald Color System
(Chicago: Paul Theobald, 1948). 4. E. Jacobson, W. C. Granville and C. E.
Foss, Color Harmony Manual 3rd ed.
(Chicago: Container Corporation of America, 1948). 5. W. C. Granville and E. Jacobson,
Colorimetric Specification of the Color
Harmony Manual from Spectrophotometric Measurements, J. Optical Society of America 34, 382 (1944). 6. C. E. Foss, D. Nickerson and W. C.
Granville, Analysis of the Ostwald Color System, J. Optical Society of America 34 361 (1944). 7. M. E. Bond and D. Nickerson, Color-Order
Systems, Munsell and Ostwald, J. Optical
Society of America 32, 709
(1942). 8. D. B. Judd, Basic Correlates of the
Visual Stimulus, in Handbook of
Experimental Psychology, S. S. Stevens, ed. (New York: John Wiley, 1951). 9. E. Buonagurio, Helen Thomas, Arts Magazine, p. 10 (Oct., 1977). |
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Fig. 7: Helen D. Thomas. ‘Multiple Image No. 2’, oil on canvas, 110 x 135 cm, 1978(Photo: William Titus, Hurlington, N.Y., U.S.A.) |
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I didn’t find any biographical dates about Helen Thomas in internet
yet. Is she still living? |
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Please leave feedback: d y
c k – b e r l i n @ t – o n l i n e . d e (Ralf Dyck, Berlin) |
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Helen Thomas' paintings are
powerfully personal and yet as universal as the musical chord. These
paintings build upon the experiences of the past rather than reject them.
Using the ostwald color sphere introduced to her by Ben Cunningham at the art
students league in her series of painting, the artist explores the illusion
of transparency and motion. Through the use of properly related colors, the
overlapping appears as a thin film slowly revolving shapes in motiom. The
unusual combinations glow as each color reinforces the other in harmony and
mood. The tension created results in defuintie relation, adding to the
synergistic effects of her work. |
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Wilhelm-
Ostwald- Archiv und Gedenkstätte Grimmaer
Strasse 25 D-04668
Grossbothen |
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tel.: +49 (0) 34384 / 71429 fax.: +49 (0) 34384 / 72691 |
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email: o s t w a l d e n e r g i e @ a o l . c o
m |
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