Whitfield, P. R. (1975). Cretivity in industry. Middlesex: Penguin Books.
Chicago Style aipamenaWhitfield, P. R. Cretivity in Industry. Middlesex: Penguin Books, 1975.
MLA aipamenaWhitfield, P. R. Cretivity in Industry. Middlesex: Penguin Books, 1975.
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