Παραπομπή APA

Duthie, J. F. (1979). Orchids of the North - Western Himalaya. Bishen Singh Mahendra Pal Singh.

Παραπομπή Chicago Style

Duthie, J F. Orchids of the North - Western Himalaya. Dehradun: Bishen Singh Mahendra Pal Singh, 1979.

Παραπομπή MLA

Duthie, J F. Orchids of the North - Western Himalaya. Bishen Singh Mahendra Pal Singh, 1979.