1. 1K. F. Baker, and D. C. Ellwood, 1980 . InContemporary Microbial Ecology . : 327 -347 . Academic Press. New York/London.
2. Manipulation of the crop and intestinal flora of the newly hatched chick
3. 3R. Freter, and S. Sasaki, 1981 . InRecent Advances in Germfree Research . : 397 -401 . Tokai University Press. Tokyo.
4. 4N. Amarger, M. J. Klug, and C. A. Reddy, 1984 . InCurrent Perspectives in Microbial Ecology . : 300 -305 . Amer. Soc. Microbiol. Washington, D.C..