1- Bamaga, O. A., Thakur, T. C. and Verma, M. L. 2000. Effect of ammonia (urea) treatment of baled wheat straw on its nutritive value. Indian J. of Animal Nutrition. 17, 8-12.
2- Bamaga, O. A., Thakur, T. C. and Verma, M. L. 2002. Laboratory investigation into the wetting of baled wheat straw stack with urea solution for ammonaition. Trans. of the ASAE. 45(1): 55-64.
3- Bhar, R., Garg, A. K. and Pathak, N. N. 1998. Effect of sealing methods on nitrogen loss during urea ammoniation of wheat straw. Indian J. of Dairy Sci. 51, 96-99.
4- Chenost, M. and Kayouli, C. 1997. Roughage utilization in warm climates. FAO. Animal Production and Health Paper 135. Rome.
5- Cottyn, B. G. and Boever, J. L. 1988. Upgrading of straw by ammoniation. Anim. Feed. Sci. Tech. 21, 287-294.
6- Jackson, M. G. 1978. Treating straw for animal feeding. FAO. Animal Production and Health Paper 10.
7- Mansbridge, R. J. and Deaville, E. R. 1995. Urea as a source of effective rumen degradable protein for high-yielding dairy cows. Breeding and Feeding the High genetic Merit Dairy Cow. 19, 102-103.
8- McGechan, M. B. and Pitt, R. E. 1990. The rewetting of partially dried grass swaths by rain: part 2. Exploratory experiments into absorption and drying. J. of Agric. Eng. Res. 45, 69-76.
9- McGechan, M. B. and Graham, R. 1993. The rewetting of partially dried grass swaths by rain: part 3. Laboratory investigation into the rewetting process. J. of Agric. Eng. Res. 55, 45-56.
10- Nguyen, X. T., Dan, C. X., Ly, L. V. and Sundstol, F. 1998. Effect of utrea concentration, moisture content, and duration of treatment on chemical composition of alkali treated rice straw. Livestock Research for Rural Development. 10(1). January.
11- Pitt, R. E. and McGechan, M. B. 1990. The rewetting of partially driedgrass swaths by rain: part 1. Lumped and distributed models of moisture fluctuation. J. of Agric. Eng. Res. 45, 55-67.
12- Raisianzadeh, M., Faizi, R., Abbasi, A. and Monazami, H. 2004. Acceptability of urea treating straw project by sheep breeders in khorasan province. in: Proceedings 2nd Conferences of Sheep and Goat. Animal Science Research Institute. Ministry of Jihad-e-Agriculture. Karaj. Iran. (In Farsi)
13- Schiere, J. B. and Ibrahim, M. N. M. 1989. Feeding of urea ammonia treated rice straw. A compilation of miscellaneous reports produced by the Straw. Utilization Project (Sri-Lanka). Pudoc. Wageningen. Netherlands.
14- Van Elderen, E., Feijter, J. D. and Van Hoven, S. P. J. H. 1972. Moisture in a grass swath. J. of Agric. Eng. Res. 17, 209-218.
)