Não informado. (1891). Contributions from the Gray Herbarium of Harvard University. Harvard University.
Chicago-Zitierstil (17. Ausg.)Não informado. Contributions from the Gray Herbarium of Harvard University. Cambridge, Mass: Harvard University, 1891.
MLA-Zitierstil (8. Ausg.)Não informado. Contributions from the Gray Herbarium of Harvard University. Harvard University, 1891.
Achtung: Diese Zitate sind unter Umständen nicht zu 100% korrekt.