The Sixth European Regional Meeting in Astronomy (VI ERMA) on "Sun and Planetary System" was held in Dubrovnik (Yugoslavia), 19-23 October 1981, sponsored by the Federal Executive Council of Yugoslavia, the IAU, IUGG, and the European Physical Society. The Scientific Organizing Committee included W. Fricke (Chairman), H. Alfven, H. Haupt, H. Kautzleben, Z. Kopal, J. Kovalevsky, V. A. Krat, L. Kresak, G. Marx, P. Melchior, P. J. Message, J. -C. Pecker, G. Sitarski, B. Sevarlic, G. Teleki, and R. M. West. The Local Organizing Committee representing the Union of Societies of Mathematicians, Physicists and Astronomers, Yugoslavia, included G. Teleki (Chairman), I. Pakvor (Vice-Chairman), Z. Knezevic (Secretary), B. Jovanovic, L. Randic, P. Ranzinger, V. Ruzdjak, B. Popovic, and B. Sevarlic. The Meeting was attended by 216 participants from 27 countries (5 continents). The scientific programme was divided into the following five sections: (1) Sun from the astronomical and physical points of view (main organizer: J. -C. Pecker); (2) Astronomical, geophysical and geodetic problems related to the Earth (main organizer: J. Kovalevsky); (3) Physics of planets, minor planets, satellites and interplanetary medium (main organizer: Z. Kopal); (4) Motions in the planetary system (main organizer: L. Kresak); (5) Three dimensional refraction (main organizer: G. Teleki). Ten invited review papers were presented in 5 plenary sessions; 20 invited papers and about 100 contributed papers were presented in parallel sessions."

E. Tengstrom G. Teleki The IAU symposium no 89, 'Refractional Influences in Astrometry and Geo- desy' , was held at the University of Uppsala, Sweden, during August 1 through August 5, 1978. It was a joint meeting of IAU and lAG, cosponsor- ed by lAG and IUGG. Considerable financial support was also given by the Swedish Natural Science Research Council, the Wallenberg Foundation in Stockholm and the University of Uppsala. The Scientific Organizing Committee included G. Teleki (chairman), W. Altenhoff (Bonn), P. Bender (Boulder), L. Hradilek (Prague), J.A. Hughes (Washington D.C.), J. Kakkuri (Helsinki), A.J. Nefedieva (Kazan), J. Saastamoinen (Ottawa), C. Sugawa (Mizusawa) and E. Tengstrom (Uppsala). The Local Organizing Committee included E. Tengstrom (chairman and con- venor), I. Ohlsson (adm. secretary and treasurer), P. Hodacs, S-G. Martensson, S. Eklund and M. O'Shaughnessy, all from Up~sala. This symposium was the first international meeting of astronomers and geodesists connected with refraction phenomena. The proceedings of this symposium contain all papers accepted by its Scientific Organizing Committee, and all discussions around them to- gether with all contributions during special workshops and round-table discussion programs.

E. Tengstrom G. Teleki The IAU symposium no 89, 'Refractional Influences in Astrometry and Geo- desy' , was held at the University of Uppsala, Sweden, during August 1 through August 5, 1978. It was a joint meeting of IAU and lAG, cosponsor- ed by lAG and IUGG. Considerable financial support was also given by the Swedish Natural Science Research Council, the Wallenberg Foundation in Stockholm and the University of Uppsala. The Scientific Organizing Committee included G. Teleki (chairman), W. Altenhoff (Bonn), P. Bender (Boulder), L. Hradilek (Prague), J.A. Hughes (Washington D.C.), J. Kakkuri (Helsinki), A.J. Nefedieva (Kazan), J. Saastamoinen (Ottawa), C. Sugawa (Mizusawa) and E. Tengstrom (Uppsala). The Local Organizing Committee included E. Tengstrom (chairman and con- venor), I. Ohlsson (adm. secretary and treasurer), P. Hodacs, S-G. Martensson, S. Eklund and M. O'Shaughnessy, all from Up~sala. This symposium was the first international meeting of astronomers and geodesists connected with refraction phenomena. The proceedings of this symposium contain all papers accepted by its Scientific Organizing Committee, and all discussions around them to- gether with all contributions during special workshops and round-table discussion programs.