内容简介：
The present volume summarizes the work of the XXIst IAU General Assembly. The discourses given during the Inaugural and Closing Ceremonies are reproduced in chapters I & III respectively. The proceedings of the two sessions of the General Assembly will be found in chapter II, which includes the Resolutions, the report of the Finance Committee and the Accounts and other aspects of the administration of the Union. Together with the report of the Executive Committee for this last triennium (chapter IV), they provide the permanent record for the Union in the period 1988-1991. This volume also contains the Commission reports from Buenos Aires compiled by the Presidents of Commissions (chapter V). The Statutes, By-Laws and a few working rules of the Union are published in chapter VI. Finally, chapter VII contains the list of countries adhering to the Union and the alphabetical, geographical and Commission membership lists of over 7350 individual IAU members. The IAU still appears to be unique among the scientific Unions in maintaining this category of individual membership which contributes in a crucial way to the spirit and the aims of the Union.