Geer, J. P. V. D. (1957). A psychological study of problem solving. s.l: s.n.
Chicago Style CitationGeer, Johan Petrus Van De. A Psychological Study of Problem Solving. s.l: s.n, 1957.
MLA CitationGeer, Johan Petrus Van De. A Psychological Study of Problem Solving. s.l: s.n, 1957.
Warning: These citations may not always be 100% accurate.