Brewer, Gwenda L. 1992. 1991 Summary Report: Location of Breeding Colonies and Evaluation of Critical Nesting Habitat for the Black Tern (Chlidonias niger) in Northwestern Minnesota: Kittson and Roseau Counties. Report to the Minnesota Department of Natural Resources. http://files.dnr.state.mn.us/eco/nongame/projects/consgrant_reports/1992/1992_brewer.pdf