Seated Woman Willem de Kooning
(1952). Pencil, pastel, and oil on two sheets of paper, 12 1/8 x 9 1/2" (30.8 x 24.2 cm). The Lauder Foundation Fund. © 2013 The Willem de Kooning Foundation / Artists Rights Society (ARS), New York
OAIster: union catalog of digital resources
MADID (Yale University Manuscripts & Archives Digital Images Database)
VIA (Harvard University Visual Information Access)
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Parker Library on the Web : Images of 6th-18th century manuscripts from Parker Library in Corpus Christi College, Camden.