American Water Works Association. (1977). The Safe Drinking Water Act Instructor's guide for water system operators seminar. American Water Works Association.
Chicago-viite (17. p.)American Water Works Association. The Safe Drinking Water Act Instructor's Guide for Water System Operators Seminar. Denver: American Water Works Association, 1977.
MLA-viite (9. p.)American Water Works Association. The Safe Drinking Water Act Instructor's Guide for Water System Operators Seminar. American Water Works Association, 1977.
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