Não informado. (1987). Miscellaneous Publications of the University of Utrecht Herbarium. University of Utrecht, Institute of Systematic Botany.
Chicago-referens (17:e uppl.)Não informado. Miscellaneous Publications of the University of Utrecht Herbarium. Utrecht, Holanda: University of Utrecht, Institute of Systematic Botany, 1987.
MLA-referens (8:e uppl.)Não informado. Miscellaneous Publications of the University of Utrecht Herbarium. University of Utrecht, Institute of Systematic Botany, 1987.
Varning: dessa hänvisningar är inte alltid fullständigt riktiga.