APA (7th ed.) Citation

DeGrood, D. H. (1982). Haeckel's theory of the unity of nature: A monograph in the history of philosophy. B. R. Gruner Pub. Co..

Chicago Style (17th ed.) Citation

DeGrood, David H. Haeckel's Theory of the Unity of Nature: A Monograph in the History of Philosophy. Amsterdam: B. R. Gruner Pub. Co., 1982.

MLA (9th ed.) Citation

DeGrood, David H. Haeckel's Theory of the Unity of Nature: A Monograph in the History of Philosophy. B. R. Gruner Pub. Co., 1982.