Holmgren, P. K., & Keuken, W. Index Herbariorum: Additions to "Herbaria of the world" ed. 6. International Bureau for Plant Taxonomy and Nomenclature.
Chicago Style (17th ed.) CitationHolmgren, Patricia K., and Wil Keuken. Index Herbariorum: Additions to "Herbaria of the World" Ed. 6. Vienna: International Bureau for Plant Taxonomy and Nomenclature.
MLA (9th ed.) CitationHolmgren, Patricia K., and Wil Keuken. Index Herbariorum: Additions to "Herbaria of the World" Ed. 6. International Bureau for Plant Taxonomy and Nomenclature.
Warning: These citations may not always be 100% accurate.