Παραπομπή σε μορφή APA (7η εκδ.)

Johnson, R. H. (1972). The concept of existence in the concluding unscientific postscript. Nijhoff.

Παραπομπή σε μορφή Chicago (17η εκδ.)

Johnson, Ralph Henry. The Concept of Existence in the Concluding Unscientific Postscript. The Hague: Nijhoff, 1972.

Παραπομπή σε μορφή MLA (9th εκδ.)

Johnson, Ralph Henry. The Concept of Existence in the Concluding Unscientific Postscript. Nijhoff, 1972.