Bibliography

Wake, D. B., K. P. Yanev, and M. M. Frelow. 1989. Sympatry and hybridization in a 'ring species': the plethodontid salamander Ensatina eschscholtzii. Otte, D., and J. A. Endler eds., Speciation and its Consequences: 134–157. Sunderland, Massachusetts, Sinauer Associates, Inc..