Wertheimer, M., & Asch, S. E. 1. . . e. (1945). Productive thinking. Harper & brothers.
Lua i Stíl Chicago (17ú heag.)Wertheimer, Max, agus Solomon Elliott 1907- ed Asch. Productive Thinking. New York: Harper & brothers, 1945.
Lua MLA (9ú heag.)Wertheimer, Max, agus Solomon Elliott 1907- ed Asch. Productive Thinking. Harper & brothers, 1945.
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