APA Edition Citation

Northrop, J., & ...[et al.]. (1939). Crystalline enzymes/2nd ed (2nd ed.). Columbia unicersity.

Chicago Edition Citation

Northrop, John, and ...[et al.]. Crystalline Enzymes/2nd Ed. 2nd ed. New york: Columbia unicersity, 1939.

MLA Edition Citation

Northrop, John, and ...[et al.]. Crystalline Enzymes/2nd Ed. 2nd ed. Columbia unicersity, 1939.