1. Allen, T. F. H. & Hoekstra, T. W. 1984. Nested and nonnested hierarchies: a significant distinction for ecological systems. In: Smith; A. W. (ed.), System methodologies and isomorphics, pp. 175–180. I. Proc. SGSR International Conference in NYC Intersystems. Seaside, CA.
2. USD A, Forest Service, General Technical Report RM-110;TFH Allen,1984
3. Allen, T. F. H. & Starr, T. B. 1982. Hierarchy: perspectives for ecological complexity. Univ. of Chicago Press, Chicago.
4. Austin, M. P. 1987. Models for the analysis of species response to environmental gradients. Vegetatio 69: 35–45.
5. Barkman, J. J. 1979. The investigation of vegetation texture and structure. In: Werger, M. J. A. (ed.), The study of vegetation, pp. 123–160. Junk, The Hague.