Παραπομπή APA

Otto, J. H., & Towle, A. (1973). Modern Biology. Richard and winston.

Παραπομπή Chicago Style

Otto, James H., και Alert Towle. Modern Biology. Holt: Richard and winston, 1973.

Παραπομπή MLA

Otto, James H., και Alert Towle. Modern Biology. Richard and winston, 1973.