Washington Water Power Company & Washington Water Power Company. Information and Special Activities Department. (1979). History of the Washington Water Power Company. Washington Water Power Company, Information and Special Activities Dept..
शिकागो शैली (17वां संस्करण) प्रशस्ति पत्रWashington Water Power Company और Washington Water Power Company. Information and Special Activities Department. History of the Washington Water Power Company. [Spokane, Wash.]: Washington Water Power Company, Information and Special Activities Dept., 1979.
एमएलए (8वां संस्करण) प्रशस्ति पत्रWashington Water Power Company और Washington Water Power Company. Information and Special Activities Department. History of the Washington Water Power Company. Washington Water Power Company, Information and Special Activities Dept., 1979.