1. BORLAND INTERNATIONAL INC. 1987, Quattto. Scotts Valley, California.
2. MAYR, E. 1969. Principles of Systematic Zoology. McGraw-Hill. New York.
3. MOORE, W.J. 1981. The Mammalian Skull. Cambridge Univ. Press, Cambridge.
4. OLSON, E.C. & MILLER, R.L. 1958. Morphological Integration. Univ. Chicago Press, Chicago.
5. PIMENTEL, R.A. & SMITH, J.D. 1986a. BIOSTAT I. A Tutorial Manual. Sigma Soft, Placentia, California.