Cita APA (7th ed.)

Watterson, R. L., & Sweeney, R. M. (1973). Laboratory studies of chick, pig, and frog embryos (3rd ed.). Burgess Pub.

Cita Chicago (17th ed.)

Watterson, Ray L., i Robert M. Sweeney. Laboratory Studies of Chick, Pig, and Frog Embryos. 3rd ed. Minneapolis, Minnesota: Burgess Pub, 1973.

Cita MLA (9th ed.)

Watterson, Ray L., i Robert M. Sweeney. Laboratory Studies of Chick, Pig, and Frog Embryos. 3rd ed. Burgess Pub, 1973.