APA aipamena

Crosby, P. B. (1979). Quality is free: The art of making quality certain. New York: A Mentor Book.

Chicago Style aipamena

Crosby, Philip B. Quality Is Free: The Art of Making Quality Certain. New York: A Mentor Book, 1979.

MLA aipamena

Crosby, Philip B. Quality Is Free: The Art of Making Quality Certain. New York: A Mentor Book, 1979.

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