Life sciences and space research XIV : proceedings of the Open meeting of the working group on space biology of the eighteenth plenary meeting of COSPAR, Varna, Bulgaria, 29 May-7 June 1975 and Symposium on gravitational physiology, Varna, Bulgaria, 30 and 31 May 1975 /
Cospar space research. 14, Proceedings of open meetings of working groups of the sixteenth plenary meeting of COSPAR, Constance, F.R.G., 23 May-5 June 1973 and resumés of the Symposium on Noctilucent Clouds and Intrplanetary Dust, Constance, F.R.G., 24 and 25 May 1973 /