Dyfyniad APA

Wertheimer, M. (1959). Productive thinking (enlarged ed.). Harper & Brothers publishers.

Dyfyniad Arddull Chicago

Wertheimer, Max. Productive Thinking. enlarged ed. New York: Harper & Brothers publishers, 1959.

Dyfyniad MLA

Wertheimer, Max. Productive Thinking. enlarged ed. Harper & Brothers publishers, 1959.

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