Columbia subject headings:
Socialism--Europe, Central--History--Sources.
Socialism--Europe, Eastern--History--Sources.
Socialist parties--Europe, Central--History--Sources.
Socialist parties--Europe, Eastern--History--Sources.
Harvard subject headings:
Socialism--Europe, Central--History--Sources.
Socialism--Europe, Eastern--History--Sources.
Socialism--Europe, Eastern--Sources.
Socialist parties--Europe, Central--History--Sources.
Socialist parties--Europe, Eastern--History--Sources.
Princeton subject headings:
Socialism--Europe, Central--History--Sources.
Socialism--Europe, Eastern--History--Sources.
Socialist parties--Europe, Central--History--Sources.
Socialist parties--Europe, Eastern--History--Sources.