Cita APA

Goodspeed, T. H., & Clausen, R. E. (1915). Variation of Flower Size in Nicotiana.

Chicago Style Citation

Goodspeed, T. H., i R. E. Clausen. Variation of Flower Size in Nicotiana. 1915.

Cita MLA

Goodspeed, T. H., i R. E. Clausen. Variation of Flower Size in Nicotiana. 1915.