Paul Klee

Art in Theory 1900-1990: An Anthology of Changing Ideas

Georg Simmel, Clive Bell, Sol Lewitt, 1993 .

Paul Klee, the thinking eye : the notebooks of Paul Klee

R. Manheim, P. Klee, Ralph Manheim, 1961 .

Theories of Modern Art: A Source Book by Artists and Critics

Kurt Schwitters, Claes Oldenburg, David Smith, 1968 .

The thinking eye

P. Klee, Paul Klee, Jürg Spiller, 1961 .