APA

Holmgran P. K., Holmgran N. H. & Barnett L. C. (1990). Index herbariorum. New York, New York, United States: The New York Botanical Garden.

Chicago

Holmgran Patricia K, Holmgran Noel H and Barnett Lisa C. 1990. Index herbariorum. New York, New York, United States: The New York Botanical Garden.

Harvard

Holmgran P. K., Holmgran N. H. and Barnett L. C. (1990). Index herbariorum. New York, New York, United States: The New York Botanical Garden.

MLA

Holmgran Patricia K, Holmgran Noel H and Barnett Lisa C. Index herbariorum. New York, New York, United States: The New York Botanical Garden. 1990.