Scotland, R., & Wortley, A. (2003). How many species of seed plants are there?
Chicago Style (17th ed.) CitationScotland, R., and A. Wortley. How Many Species of Seed Plants Are There? 2003.
MLA (9th ed.) CitationScotland, R., and A. Wortley. How Many Species of Seed Plants Are There? 2003.
Warning: These citations may not always be 100% accurate.