Bell, F. G. (2007). Basic enviornmental and engineering geology. Whittles Publishing.
Dyfyniad Arddull ChicagoBell, F G. Basic Enviornmental and Engineering Geology. U. K: Whittles Publishing, 2007.
Dyfyniad MLABell, F G. Basic Enviornmental and Engineering Geology. Whittles Publishing, 2007.
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