Nitrogen, phosphorus and sulphur--global cycles : report from a project on biogeochemical cycles initiated by the Scientific Committee on Problems of the Environment (SCOPE) of ICSU, arranged by the Swedish SCOPE Committee of the Royal Swedish Academy of Sciences, Örsundsbro, Sweden, 14-18 December 1975. - Svensson, Bo H; Söderlund, Rune (Ecological bulletins, 1976)