The list of foreign historical literature, bought by the above-mentioned libraries in 1975, is prepared each year according to the same principles. Literature is classified according to the states or groups of states or nations, vvith the group of »general vvorks« at the head. If the groups are large, they are further divided into sub-groups according to individual periods or other aspects. The books are cited vvith the bibliographic description, which is normally used in libraries. At the end of each description there is the abbreviation of the library, vvhere the book is kept, and its signature in the library.