• Adler (1994), S.880
• Binz (1986), S.501
• Flora Gallica (2014), S.134
• Flora Helvetica (2012), Nr.2378
• Flora Italiana (2.7.2022)
• Haynes, Flora of North America (1.7.2022)
• Hess (1976ff), Bd. 1, S.223
• info flora (2.7.2022)
• Markgraf (1981), S.188f.
• Oberdorfer (2001), Nr.157
• Pignatti (1982), Vol.3, Nr.4506
• Rothmaler (2002), S.135
• Talavera (2008)
• Tela Botanica (2.7.2022)
• Word Flora Online (1.7.2022)

Foto: John Robert McPherson, CC BY-SA 4.0 , via Wikimedia Commons