Woldeyohannes และ Wassie Haile. (2006) Investigation on the nitrification inhibition potential of some ethiopian medicinal herbs for improving n-use efficiency and yield of wheat /. Kasetsart University,:ม.ป.ท.Woldeyohannes และ Wassie Haile. 2006. Investigation on the nitrification inhibition potential of some ethiopian medicinal herbs for improving n-use efficiency and yield of wheat /. ม.ป.ท.:Kasetsart University,;Woldeyohannes และ Wassie Haile. Investigation on the nitrification inhibition potential of some ethiopian medicinal herbs for improving n-use efficiency and yield of wheat /. ม.ป.ท.:Kasetsart University, 2006. Print.