1. Afifi, A. A. and Clark, V. 1984. Computer-aided Multivariate Analysis. Lifetime Learning Publications, Belmont, Calif., p. 458.
2. Asahina, E. 1978. Freezing processes and injury in plant cells, pp. 17–37. In: Li, P. H. and Sakai, A. (Eds) Plant Cold Hardiness and Freezing Stress. Academic Press, Inc., London.
3. Bonner, F. T., McLemore, B. F. and Barnett, J. P. 1974. Presowing treatment of seed to speed germination, p. 883. In: Seeds of Woody Plants in the United States. USDA/FS Agr. Handbook, Washington, D.C. 450.
4. Burton, G. W. 1980. Utilization of hybrid vigor, pp. 184–203. In: Wood, D. R. (Ed) Crop Breeding. American Society of Agronomy, Madison, WI.
5. Duncan, P. D. 1994. First-year growth, morphology, and freeze hardiness of pure species and hybrid taxa of Pinus elliottii and Pinus caribaea. M.S. thesis, University of Florida, Gainesville, p. 55.