5Liu C J, Ilvesniemi H, Berg B, et al. 2003. Aboveground litterfall in Eurasian forests. Journal of Forestry Research, 14 ( I ) : 27 - 34.
6Nuberg I K, Evans D G. 1993. Alley cropping and analog forest for soil conversation in the dry uplands of Sri Lanka. Agroforestry System, 24 (3): 247-269.