APA (7th ed.) Citation

Crofton, W. M. (1939). The true nature of viruses: (with appendix) (2d and enl. ed.). Staple Press.

Chicago Style (17th ed.) Citation

Crofton, W. M. The True Nature of Viruses: (with Appendix). 2d and enl. ed. London: Staple Press, 1939.

MLA (9th ed.) Citation

Crofton, W. M. The True Nature of Viruses: (with Appendix). 2d and enl. ed. Staple Press, 1939.