Spencer, D. A. (1974). The National Pesticide monitoring program: An overview of the first ten years of the program’s operation. Washington: National Agricultural Chemicals Association.
Trích dẫn kiểu ChicagoSpencer, Donald A. The National Pesticide Monitoring Program: An Overview of the First Ten Years of the Program’s Operation. Washington: National Agricultural Chemicals Association, 1974.
Trích dẫn MLASpencer, Donald A. The National Pesticide Monitoring Program: An Overview of the First Ten Years of the Program’s Operation. Washington: National Agricultural Chemicals Association, 1974.
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