Towards a new relationship of man and nature in temperate lands. Part III. Changes due to introduced species 1967
Towards a new relationship of man and nature in temperate lands. Part 2. Town and country planning problems 1967
Towards a new relationship of man and nature in temperate lands. Part 1. Ecological impact of recreation and tourism upon temperate environment 1967
Conservation of nature and natural resources in modern African states : report of a symposium 1963 Watterson, Gerald G. |
Conférence internationale pour la protection de la nature, Brunnen, 28 juin - 3 juillet 1947 : procès-verbaux, résolutions et rapports 1947 Büttikofer, Johann |