7Ceballos Lascurain H. The Future of Eco - Tourism[J ]. Mexico Journal, 1987(1): 13-14.
8Buckley R. A Framework for Eco - toturism[J]. Annals of Tourism Research, 1994,21 (3) :661 -669.
9Shery Ross, Geoffery Wall . Eco-tourism:Towards Congruence between Theory and Practice[J]. Tourism Management, 1999, (20) : 123- 132.
10Pearce DG. Alternative Tourism. Concepts, Classifications, and Questions. Tourism Alternatives: Potential and Problems in the Development of Tourism[M]. Philadelphia: University of Pennsylvania Press, 1992,15 - 30.