المؤلفون: Finch, R. M., Kepner, Dana E., Klevorn, W. J., Johnson, W. Scott, Haskins, C. A., Towne, W. W., McEvoy, J. W., Waterman, Earle L.

المصدر: Journal (American Water Works Association), 1933 Feb 01. 25(2), 282-291.

URL الوصول: https://www.jstor.org/stable/41225816