Lundgren, L. W. (1999). Environmental geology (2nd ed.). Prentice-Hall of India.
Dyfyniad Arddull ChicagoLundgren, Lawrence W. Environmental Geology. 2nd ed. New Jersey: Prentice-Hall of India, 1999.
Dyfyniad MLALundgren, Lawrence W. Environmental Geology. 2nd ed. Prentice-Hall of India, 1999.
Rhybudd: Mae'n bosib nad yw'r dyfyniadau hyn bob amser yn 100% cywir.