APA (7th ed.) Citation

Craig, R. T., & Dawson, E. Y. (1948). A new variety of Mammillaria Scrippsiana ([Sonderdr.].).

Chicago Style (17th ed.) Citation

Craig, Robert T., and Elmer Yale Dawson. A New Variety of Mammillaria Scrippsiana. [Sonderdr.]. 1948.

MLA (9th ed.) Citation

Craig, Robert T., and Elmer Yale Dawson. A New Variety of Mammillaria Scrippsiana. [Sonderdr.]. 1948.

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