APA (7th ed.) Citation

Poellnitz, K. v. (1937). Five little Known species of the genus Haworthia, Duval ([Sonderdr.].).

Chicago Style (17th ed.) Citation

Poellnitz, Karl von. Five Little Known Species of the Genus Haworthia, Duval. [Sonderdr.]. 1937.

MLA (9th ed.) Citation

Poellnitz, Karl von. Five Little Known Species of the Genus Haworthia, Duval. [Sonderdr.]. 1937.

Warning: These citations may not always be 100% accurate.