APA (7th ed.) Citation

Lewis, W. H. (1968). Two new species of Polygala endemic to Panama ([Sonderdr.].).

Chicago Style (17th ed.) Citation

Lewis, Walter Hepworth. Two New Species of Polygala Endemic to Panama. [Sonderdr.]. 1968.

MLA (9th ed.) Citation

Lewis, Walter Hepworth. Two New Species of Polygala Endemic to Panama. [Sonderdr.]. 1968.

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