1. Akashi N (1996) The spatial pattern and canopy-understory association of trees in a cool temperate, mixed forest in western Japan. Ecol Res 11:311–319
2. Allen TFH, Starr TB (1982) Hierarchy: perspectives for ecological diversity. University of Chicago Press, Chicago, IL
3. Asadollahi F (2001) Study of Hyrcanian plant association in north Iranian forest. 1st national conference of north forest management and sustainable development, Ramsar, Iran
4. Barnes BV (1998) Forest ecology. Wiley, New York. 773 pp
5. Busing R (1991) A spatial model of forest dynamics. Vegetatio 92:167–179