Παραπομπή σε μορφή APA (7η εκδ.)

Keene, G. B. (1961). Abstract sets and finite ordinals: An introduction to the studu of set theory. Pergamon Press.

Παραπομπή σε μορφή Chicago (17η εκδ.)

Keene, G. B. Abstract Sets and Finite Ordinals: An Introduction to the Studu of Set Theory. Oxford, New York: Pergamon Press, 1961.

Παραπομπή σε μορφή MLA (9th εκδ.)

Keene, G. B. Abstract Sets and Finite Ordinals: An Introduction to the Studu of Set Theory. Pergamon Press, 1961.