Cita APA (7a ed.)
Wickelgren, W. A. (1974). How to Solve Problems: Elements of a Theory of Problems and Problem Solving.
Cita estilo Chicago (17a ed.)
Wickelgren, Wayne A. How to Solve Problems: Elements of a Theory of Problems and Problem Solving. 1974.
Cita MLA (9a ed.)
Wickelgren, Wayne A. How to Solve Problems: Elements of a Theory of Problems and Problem Solving. 1974.
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