APA

Hagan H. R., . (1951). Embryology of the viviparous insects. New York: Ronald Press.

Chicago

Hagan Harold Raymond, . 1951. Embryology of the viviparous insects. New York: Ronald Press.

Harvard

Hagan H. R., . (1951). Embryology of the viviparous insects. New York: Ronald Press.

MLA

Hagan Harold Raymond, . Embryology of the viviparous insects. New York: Ronald Press. 1951.