1. IUCN (1974). Biotic Provinces of the World: Further Development of a System for Defining and Classifying Natural Regions for Purposes of Conservation. IUCN Occasional Paper No. 9, 57 pp., mimeogr., 7 sketch-maps.
2. Willard Hon. B. E. (in press). Ethics of biospheral survival: a dialogue, Part I. Pp. 506–22, in Growth Without Ecodisasters? (Ed. Nicholas Polunin). Macmillan, London & Basingstoke, and Halsted-Wiley, New York.
3. IUCN (1975 b). World Directory of National Parks and Other Protected Areas. International Union for Conservation of Nature and Natural Resources, 1110 Morges, Switzerland: Loose-leaf, with occasional sketch-maps, etc.
4. Haeckel E. H. (1873). Natural History of Creation. [Not available for checking.]
5. The ecological survey;Grimsdell;Parks,1977