Cobb, B., & Foster, L. L. (1960). A field guide to the ferns and their related famillies of Northeastern and central North America: With a section on species also found in the British Isles and Western Europe (2. printing.). Houghton Mifflin Company.
Chicago-Zitierstil (17. Ausg.)Cobb, Boughton, und Laura Louise Foster. A Field Guide to the Ferns and Their Related Famillies of Northeastern and Central North America: With a Section on Species Also Found in the British Isles and Western Europe. 2. printing. Boston, Massachusetts: Houghton Mifflin Company, 1960.
MLA-Zitierstil (9. Ausg.)Cobb, Boughton, und Laura Louise Foster. A Field Guide to the Ferns and Their Related Famillies of Northeastern and Central North America: With a Section on Species Also Found in the British Isles and Western Europe. 2. printing. Houghton Mifflin Company, 1960.