- Radio Free Europe/Radio Liberty, Inc - Research Institute8
- Pallai, Péter5
- Bortstieber, Gertrud4
- Dallin, David J.3
- Hanák, Péter3
- Samizdat Archives3
- Nóvé, Béla2
- United States. Department of State2
- American Federation of Labor1
- Ascoli, Max1
- Balkan Section1
- Balogh, Eva S.1
- Balzak, S. S.1
- Berdiaev, Nikolaĭ1
- Berlin, Isaiah1
- Bishop, Robert1
- Blau, Joseph L.1
- British Broadcasting Corporation, Written Archive Centre1
- Bulgarian Unit1
- Bullitt, William C.1