Brinton, E. P.; Beck, D E.; and Allred, D. M.
"Identification of the adults, nymphs and larvae of ticks of the genus Dermacentor Koch (Ixodidae) in the western United States,"
Brigham Young University Science Bulletin, Biological Series: Vol. 5
, Article 1.
Available at: http://scholarsarchive.byu.edu/byuscib/vol5/iss4/1