APA Citation

Geer ,Van De J.P. (1926). A psychologycal study of problem solving. Rotterdam: s.n.

Chicago Style Citation

Geer ,Van De J.P. A Psychologycal Study of Problem Solving. Rotterdam: s.n, 1926.

MLA Citation

Geer ,Van De J.P. A Psychologycal Study of Problem Solving. Rotterdam: s.n, 1926.

Warning: These citations may not always be 100% accurate.