Ecology of lake Chad : A tropical shallow lake (Africa) /Lévêque, Christian VARIATION SAISONNIERE PRODUCTIVITE BIOLOGIQUE BIOMASSE ECOSYSTEME LACUSTRE Center of International Projects.GKNT 1982 text https://www.documentation.ird.fr/hor/fdi:03968 fdi:03968 Lévêque Christian. Ecology of lake Chad : A tropical shallow lake (Africa). Center of International Projects.GKNT, 1982, 163-187 International Scientific Workshop on Ecosystem Dynamics in Freshwater Wetlands and Shallow Water Bodies, Minsk; Pinsk; Tskhaltoubo (SUN), 1981:07/12-26 EN CAMEROUN EXTREME NORD LOGONE ET CHARI TCHAD LAC TCHAD NIGER NIGERIA