Phonethep P, Preston T R and Leng R A 2016: Effect on feed intake, digestibility, N retention and methane emissions in goats of supplementing foliages of cassava (Manihot esculenta Crantz) and Tithonia diversifolia with water spinach (Ipomoea aquatica). Livestock Research for Rural Development. Volume 28, Article #72. Retrieved , from http://www.lrrd.org/lrrd28/5/phon28072.html