2 literature references for Baeolophus inornatus (Gambel, 1845):

Author: Clements, James F.
Year: 2007
Title:
Source: The Clements Checklist of Birds of the World, Sixth Edition
Author: Cicero, Carla
Year: 2000
Title: Oak Titmouse (Baeolophus inornatus) and Juniper Titmouse (Baeolophus ridgwayi)
Source: The Birds of North America, no. 485