Clay and O'Brien counties lie in a section of Iowa which have received little attention from ornithologists. O’Brien is the more westerly; it is the second from the western boundary of the state, with Clay County adjoining it on the east; and each lies within one county of the Minnesota state line.
Proceedings of the Iowa Academy of Science
©1917 Iowa Academy of Science, Inc.
Gabrielson, Ira N.
"A List of the Birds Observed in Clay and O'Brien Counties, Iowa,"
Proceedings of the Iowa Academy of Science, 24(1), 259-272.
Available at: https://scholarworks.uni.edu/pias/vol24/iss1/40