Tran Hiep, Dang Vu Hoa and Nguyen Xuan Trach 2011 Mitigation of methane emission by means of oil and nitrate supplement in diets of growing cattle.  Workshop on Reducing Greenhouse Gas Emissions from Livestock and Soils (Editors: Reg Preston and Sisomphone Southavong). National Institute of Animal Science, Hanoi, 14-15 November 2011. httm://www.mekarn.org/workshops/GHG-CC/hiep.hua.htm