Dyfyniad APA

Whiting, P. H. (1957). 5 great rules of selling (rev ed.). McGraw-Hill.

Dyfyniad Arddull Chicago

Whiting, Percy H. 5 Great Rules of Selling. rev ed. New York: McGraw-Hill, 1957.

Dyfyniad MLA

Whiting, Percy H. 5 Great Rules of Selling. rev ed. McGraw-Hill, 1957.

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