4 literature references for Parus inornatus Gambel, 1845:

Year: 1996
Source: database, NODC Taxonomic Code
Author: Banks, R. C., R. W. McDiarmid, and A. L. Gardner
Year: 1987
Title: Checklist of Vertebrates of the United States, the U.S. Territories, and Canada
Source: Resource Publication, no. 166
Author: American Ornithologists' Union
Year: 1957
Source: Check-list of North American Birds, 5th Edition
Author: Cicero, Carla
Year: 2000
Title: Oak Titmouse (Baeolophus inornatus) and Juniper Titmouse (Baeolophus ridgwayi)
Source: The Birds of North America, no. 485