Williams, P. T. (2005). Waste treatment and disposal (Second edition.). John Wiley.
Dyfyniad Arddull ChicagoWilliams, Paul T. Waste Treatment and Disposal. Second edition. Chichester: John Wiley, 2005.
Dyfyniad MLAWilliams, Paul T. Waste Treatment and Disposal. Second edition. John Wiley, 2005.
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