Dyfyniad APA

Sheehy, E. P. (1986). Guide to reference books (10th ed.). American Library Association.

Dyfyniad Arddull Chicago

Sheehy, Eugene Paul. Guide to Reference Books. 10th ed. Chicago: American Library Association, 1986.

Dyfyniad MLA

Sheehy, Eugene Paul. Guide to Reference Books. 10th ed. American Library Association, 1986.

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