Zappia, H., & Fisher, G. T. (1997). Water-quality assessment of the Potomac River Basin: Analysis of available pesticide data, 1972-90. U.S. Geological Survey.
Chicago Style (17th ed.) CitationZappia, Humbert, and Gary T. Fisher. Water-quality Assessment of the Potomac River Basin: Analysis of Available Pesticide Data, 1972-90. Baltimore, Maryland: U.S. Geological Survey, 1997.
MLA (9th ed.) CitationZappia, Humbert, and Gary T. Fisher. Water-quality Assessment of the Potomac River Basin: Analysis of Available Pesticide Data, 1972-90. U.S. Geological Survey, 1997.
Warning: These citations may not always be 100% accurate.