Cita APA (7a ed.)

Skelly, J. M., & Alexander, S. A. (1987). Diagnosing injury to Eastern forest trees: A manual for identifying damage caused by air pollution, pathogens, insects, and abiotic stresses. Pennsylvania State University Press.

Cita Chicago Style (17a ed.)

Skelly, John M., y Samuel A. Alexander. Diagnosing Injury to Eastern Forest Trees: A Manual for Identifying Damage Caused by Air Pollution, Pathogens, Insects, and Abiotic Stresses. University Park: Pennsylvania State University Press, 1987.

Cita MLA (9a ed.)

Skelly, John M., y Samuel A. Alexander. Diagnosing Injury to Eastern Forest Trees: A Manual for Identifying Damage Caused by Air Pollution, Pathogens, Insects, and Abiotic Stresses. Pennsylvania State University Press, 1987.