References
- Harrington, H. D. 1964: Manual of the Plants of Colorado, for the Identification of the Ferns and Flowering Plants of the State. 2nd Ed. Sage Books, The Swallow Press, Inc., Chicago. 666 pp.
- Heckard, L. R. 1962: Root parasitism in Castilleja. Bot. Gaz., 124: 21–29.
- Kuijt, J. 1969: The Biology of Parasitic Flowering Plants. University of California Press, Berkeley and Los Angeles. 246 pp.
- Malcolm, W. M. 1966: Root parasitism of Castilleja coccinea. Ecology, 47: 179–186.
- Sass, J. E. 1961: Botanical Microtechnique. Iowa State University Press, Ames, Iowa. 228 pp.
- Weber, W. A. 1967: Rocky Mountain Flora. Rev. Ed. University of Colorado Press, Boulder, Colorado. 437 pp.