Morgan, R. P. C. (1995). Soil erosion and conservation (2nd ed.). Longman ; J. Wiley.
Lua i Stíl Chicago (17ú heag.)Morgan, R. P. C. Soil Erosion and Conservation. 2nd ed. Harlow, Essex, England : New York, NY: Longman ; J. Wiley, 1995.
Lua MLA (9ú heag.)Morgan, R. P. C. Soil Erosion and Conservation. 2nd ed. Longman ; J. Wiley, 1995.