Citazione APA

(1972). New book of knowledge V.20: W.X.Y.Z. Grolier Incorporated.

Stile di citazione Chicago

New Book of Knowledge V.20: W.X.Y.Z. New York: Grolier Incorporated, 1972.

Citazione MLA

New Book of Knowledge V.20: W.X.Y.Z. Grolier Incorporated, 1972.