Ballentine, R.K. and L.J. Guarraia (editors)(1977). The Integrity of Water.Arhivirano 2014-12-14 na Wayback Machine-u Proceedings of a Symposium, March 10–12, 1975, U.S. Environmental Protection Agency, Washington, D.C. EPA Publication No. 832-R-75-103.
Ballentine, R.K. and L.J. Guarraia (editors)(1977). The Integrity of Water.Arhivirano 2014-12-14 na Wayback Machine-u Proceedings of a Symposium, March 10–12, 1975, U.S. Environmental Protection Agency, Washington, D.C. EPA Publication No. 832-R-75-103.