@book{12925,
	author = {D.N. Rao, R.S. Ambasht, K.L. Mukherjee, R.S.Dwivedi, P.V. Ananthakrishnan},
	title = {Ecology Study of Ecosystems },
	publisher = {A.H. Wheeler,},
	year = {1970},
	address = {Delhi :}
}