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                           for prioritizing the inspection of sewers : Knowledge base formulation and evaluation.”
                           Journal of Water Resources Planning and Management, Vol. 128, No. 2, pp. 121-129.10.1061/(ASCE)0733-9496(2002)128:2(121)Hahn,
                           M. A., Palmer, R. N., Merrill, M. S. and Lukas, A. B. (2002). “Expert system for prioritizing
                           the inspection of sewers : Knowledge base formulation and evaluation.” Journal of
                           Water Resources Planning and Management, Vol. 128, No. 2, pp. 121-129.
