The Flynn, Daniel J. Nalco Company text New York McGraw-Hill c2009 3rd ed. monographic P-43-16 Illus Nalco Company ; Daniel J. Flynn, editor. 0 0 0 546_220000000000000_NAL Factory and trade waste Purification MCE Sewage Purification Water use Water Purification 546.22 NAL 0071548831 (hbk.) 9780071548830 (hbk.) http://www.columbia.edu/cgi-bin/cul/resolve?clio9621843 http://www.columbia.edu/cgi-bin/cul/resolve?clio9621843