Harshberger, J. W. (1958). Phytogeographic survey of North America: A consideration of the phytogeography of the North American continent, including Mexico, Central America and the West Indies, together with the evolution of North American plant distribution (2. ed.). Engelmann.
Chicago-Zitierstil (17. Ausg.)Harshberger, John William. Phytogeographic Survey of North America: A Consideration of the Phytogeography of the North American Continent, Including Mexico, Central America and the West Indies, Together with the Evolution of North American Plant Distribution. 2. ed. Weinheim/Bergstr: Engelmann, 1958.
MLA-Zitierstil (9. Ausg.)Harshberger, John William. Phytogeographic Survey of North America: A Consideration of the Phytogeography of the North American Continent, Including Mexico, Central America and the West Indies, Together with the Evolution of North American Plant Distribution. 2. ed. Engelmann, 1958.