Henry, S. L. (1989). Paul Klee's pictorial mechanics from physics to the picture plane. Pantheon.
Chicago-viite (17. p.)Henry, Sara Lynn. "Paul Klee's Pictorial Mechanics from Physics to the Picture Plane." Pantheon 1989.
MLA-viite (8. p.)Henry, Sara Lynn. "Paul Klee's Pictorial Mechanics from Physics to the Picture Plane." Pantheon, 1989.
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