Dyfyniad APA

Gale Research Company. (1990). Book review index. Gale Research.

Dyfyniad Arddull Chicago

Gale Research Company. Book Review Index. Detroit: Gale Research, 1990.

Dyfyniad MLA

Gale Research Company. Book Review Index. Gale Research, 1990.

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