APA (7th ed.) Citation

Mai, W. F., & Lyon, H. H. (1975). Pictorial key to genera to plant-parasitic nematodes (4. ed., rev.). Comstock.

Chicago Style (17th ed.) Citation

Mai, William F., and Howard H. Lyon. Pictorial Key to Genera to Plant-parasitic Nematodes. 4. ed., rev. Ithaca, NY: Comstock, 1975.

MLA (9th ed.) Citation

Mai, William F., and Howard H. Lyon. Pictorial Key to Genera to Plant-parasitic Nematodes. 4. ed., rev. Comstock, 1975.