APA (7e ed.) Bronvermelding

Gray, D. E. (1966). Man and his physical world. D. Van Nostrand.

Chicago (17e ed.) Bronvermelding

Gray, Dwight E. Man and His Physical World. Princeton: D. Van Nostrand, 1966.

MLA (9e ed.) Bronvermelding

Gray, Dwight E. Man and His Physical World. D. Van Nostrand, 1966.