↑ Baker, Moses N. (1981). The Quest for Pure Water: the History of Water Purification from the Earliest Records to the Twentieth Century. 2nd Edition. Vol. 1. Denver: American Water Works Association, 64-80.
↑ “Allen Hazen.” (1930). Jour. American Water Works Association. 22:9, 1268-70.
↑ Fuller, George W. (1902). “The Filtration Works of the East Jersey Water Company, at Little Falls, New Jersey.” Transactions of the ASCE. 29 (February)): 153-202.
↑ Baylis, John R. (1959). "Review of Filter Bed Design and Methods of Washing." Journal AWWA. 51:11 1433-54.
