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Elliott, Henry W. (1882). A Monograph of the Seal Islands. Washington, D.C.: Government Printing Office. p. 19. Archived from the original on March 30, 2015. Retrieved May 31, 2020.
Cecil, John; Sanchez, Connie; Stenhouse, Iain; Hartzler, Ian (2009). "United States of America"(PDF). In Devenish, C.; Díaz Fernández, D. F.; Clay, R. P.; Davidson, I.; Yépez Zabala, I. (eds.). Important Bird Areas Americas - Priority sites for biodiversity conservation. Quito, Ecuador: BirdLife International. p. 374. ISBN978-9942-9959-0-2. Archived(PDF) from the original on October 16, 2012. Retrieved July 6, 2011.