Dyfyniad APA

Crosby, P. B. (1979). Quality is free: The art of making quality certain. McGraw-Hill.

Dyfyniad Arddull Chicago

Crosby, Philip B. Quality Is Free: The Art of Making Quality Certain. New York: McGraw-Hill, 1979.

Dyfyniad MLA

Crosby, Philip B. Quality Is Free: The Art of Making Quality Certain. McGraw-Hill, 1979.

Rhybudd: Mae'n bosib nad yw'r dyfyniadau hyn bob amser yn 100% cywir.