1. Operation and maintenance of municipal waste treatment plants;Michel;J. Water Pollut. Control Fed.,1969
2. Variability of waste treatment plant performance;Thomann,1970
3. Need for Improved Operation and Maintenance of Municipal Waste Treatment Plants;Comptroller General's Office;Report B-166506,1970
4. Federal Guidelines—Design, Operation and Maintenance of Waste Water Treatment Facilities;Federal Water Quality Administration,1970