Não informado. (1892). Contributions from the Botanical Laboratory of the University of Pennsylvania. University of Pennsylvania.
Chicago-Zitierstil (17. Ausg.)Não informado. Contributions from the Botanical Laboratory of the University of Pennsylvania. Philadelphia, Pa: University of Pennsylvania, 1892.
MLA-Zitierstil (8. Ausg.)Não informado. Contributions from the Botanical Laboratory of the University of Pennsylvania. University of Pennsylvania, 1892.
Achtung: Diese Zitate sind unter Umständen nicht zu 100% korrekt.