51.
China National Report on Geodesy. 1987 - 1990
/ IUGG XX General Assembly IAG, Vienna, August 11-24, 1991
Beijing: Meteorological Press, 1991
Signatura: K46854
52.
China National Report /1987 - 1990/ on Seismology and Physics of the Earth's Interior, for the 20. General Assembly of IUGG, Vienna, Austria, 1991
/ IUGG XX General Assembly IAG, Vienna, August 11-24, 1991
Beijing: Chin. Nat. Committee, 1991
Signatura: K46802
53.
China National Report (1987 - 1990) on Meteorology and Atmospheric Physics
/ IUGG XX General Assembly IAG, Vienna, August 11-24, 1991
Beijing: Chinese Nat. Comm., 1991
Signatura: K46804
54.
China National report (1987 - 1990) on Geomagnetism and Aeronomy
/ IUGG XX General Assembly IAG, Vienna, August 11-24, 1991
Beijing: Chinese Nat.Committee, 1991
Signatura: K46803
55.
Canadian National Report to the IUGG 1987 - 90
/ IUGG XX General Assembly IAG, Vienna, August 11-24, 1991
Ottawa: National Research Council, 1991
Signatura: K46855
56.
Austria. IAG - Report of the Austrian Geodetic Commission
/ IUGG XX General Assembly IAG, Vienna, August 11-24, 1991
Vienna: Bundesamt für Eich- und Vermessungswesen, 1991
Signatura: K46858
57.
Activity Report 1987 - 1990 of Commission 8: International Coordination of Space Techniques for Geodesy and Geodynamics (CSTG)
/ IUGG XX General Assembly IAG, Vienna, August 11-24, 1991
Wien: IAG Wien, 1991
Signatura: K46819