1. Phosphate Compounds Occurring in Illinois Surface Waters;Dietz;Proc. 12th Ind. Waste Conf.; Purdue University,1958
2. Studies on the Occurrence and Degradation of Condensed Phosphate in Surface Waters;Engelbrecht;Sew. & Ind. Wastes,1959
3. Determination of Inorganic Phosphate;Martin;Anal. Chem.,1949
4. Determination of Orthophosphate, Hydrolyzable Phosphate, and Total Phosphate in Surface Waters;AASGP Committee Report;Jour. AWWA,1958