International Energy Agency, Organisation for Economic Co-operation and Development, European Conference of Ministers of Transport, European Commission
organized by the Commission of the European Communities, Directorate-General for Science, Research, and Development, DG XII/D, Environment Programme, Joint Research Centre, Environment Institute ; cosponsored by the Danish Centre for Atmospheric Research ; edited by Giambattista Restelli and Giovanni Angeletti
organized jointly by the CEC and the Institute for Soil Fertility, Haren (Gr.), and held in Groningen, Netherlands, on June 12 and 13, 1980 ; sponsored by the Commission of the European Communities, Directorate-General for Agriculture, and Directorate-General for Research, Science and Education ; edited by T.W.G. Hucker and G. Catroux