Erickson, S. L. (1999). Fundamentals of environmental management. John Wiley.
Dyfyniad Arddull ChicagoErickson, Steven L. Fundamentals of Environmental Management. New York: John Wiley, 1999.
Dyfyniad MLAErickson, Steven L. Fundamentals of Environmental Management. John Wiley, 1999.
Rhybudd: Mae'n bosib nad yw'r dyfyniadau hyn bob amser yn 100% cywir.