Inthapanya S and Preston T R 2015: Effect of source of supplementary dietary protein and feed offer level (ad libitum or restricted) on feed intake, digestibility and N balance in local “Yellow” cattle fed rice straw treated with urea as basal diet. Livestock Research for Rural Development. Volume 27, Article #45. Retrieved , from http://www.lrrd.org/lrrd27/3/sang27045.htm