APA (7th ed.) Citation

Harper, R. (1948). Existentialism: A Theory of Man. Harvard University Press. https://doi.org/10.4159/harvard.9780674497375

Chicago Style (17th ed.) Citation

Harper, Ralph. Existentialism: A Theory of Man. Cambridge, Mass: Harvard University Press, 1948. https://doi.org/10.4159/harvard.9780674497375.

MLA (9th ed.) Citation

Harper, Ralph. Existentialism: A Theory of Man. Harvard University Press, 1948. https://doi.org/10.4159/harvard.9780674497375.