1. Anderson , L. E. ( 1968 ) A mathematical model for the optimization of a wastes management system , University of California at Berkeley, Sanitary Engineering Research Laboratory, SERL Report No. 68-1 .
2. Walker , W. , Aquilina , M. and Schur , D. ( 1974 ) Development and use of a fixed charge programming model for regional solid waste planning presented at the 46th joint meeting of the Operation Research Society of America and the Institute of Management Sciences , Puerto Rico .