1. Proc. 13th Conf. Photovoltaic Specialists;Barnett,1978
2. Experiments on Ge-GaAs heterojunctions
3. Workshop Montpellier;Gordillo,1983
4. Proc. 16th Conf. Photovoltaic Specialists;Hewig,1982
5. Proc. 3rd EC Conf. Photovoltaic Solar Energy;Pfisterer,1981