7Emil Cienciala,et al.The effect of a north-facing forest edge on tree water use in a boreal Scots pine stand,《Canadian Journal of Forest Research.》,Apr 2002.Vol.32,Iss.4; pg.693,10 pgs
8Richard C Schultz.Forest Hydrology:An Introduction to Water and Forests.Forest Science.Bethesda:Apr 2003.Vol.49,Iss.2; P.336