Conference in the Matter of Pollution of the Interstate Waters of the Colorado River and Its Tributaries in the States of California, Colorado, Utah, Arizona, Nevada, New Mexico, and Wyoming (7th : 1972 : Denver)
Conference in the Matter of Pollution of the Interstate Waters of the Colorado River and Its Tributaries-Colorado, New Mexico, Arizona, California, Nevada, Wyoming and Utah (7th : 1972 : Las Vegas, Nev.)