P. W.  Ball, ?Hills oak (Quercus ellipsoidalis) in southern Ontario, Canada?, Canadian Field-Naturalist, vol. 95, pp. 281-286, 1981.

R. J.  Jensen, ?A preliminary numerical analysis of the red oak complex in Michigan and Wisconsin USA?, Taxon, vol. 26, pp. 399-407, 1977.

C.  Dutech, Sork, V. L., Irwin, A. J., Smouse, P. E., and Davis, F. W., ?Gene flow and fine-scale genetic structure in a wind-pollinated tree species Quercus lobata (Fagaceaee)?, American Journal of Botany, vol. 92, pp. 252-261, 2005.