North American flora - New York Botanical Garden (New York Botanical Garden, 1917)

Phytologia - Moldenke, Harold N. (Harold Norman), 1909 -1996 (H.A. Gleason and H.N. Moldenke, 1968)

Prodromus systematis naturalis regni vegetabilis, sive, Enumeratio contracta ordinum generum specierumque plantarum huc usque cognitarium, juxta methodi naturalis, normas digesta - Candolle, Augustin Pyramus de, 1778 -1841 (Sumptibus Sociorum Treuttel et Würtz, 1849)

SIDA, contributions to botany - Mahler, William F. (W. F. Mahler, etc.], 1998)

Synopsis der mitteleuropaïschen flora - Graebner, Paul, 1871 -1933 (W. Engelmann, 1896)