Sustainable development : learning for tomorrow's world : international conference on environmental education, Bo, Telemark, Norway, June 8-10 1988 : report 1988 Fjortoft, Ingunn | Halle, Per Kristian |
Environmental conservation education in the school curriculum in East European countries : proceedings and documentation, International Seminar of the East-Europe Committee, IUCN Commission on Education, Kroscienko-Szczawnica, Poland, 22-28 June 1972 1973