1. Koenig , L. Studies Relating to Market Projections for Advanced Waste Treatment Federal Water Pollution Control Administration Publication WP-20-AWTR-17 Washington, D.C. 1966
2. Wigley , C. G. To What Degree Must Sewage Be Purified? Proceedings, AWWA 1912 269
3. Relation of Water Supply and Sewage Disposal;Norcom;Jour. AWWA,1925
4. Stream Pollution and Its Effects;Veatch;Jour. AWWA,1927
5. Wastewater Reclamation as a Water Resource;Metzler;Jour. AWWA,1968