- Open Society Archives at Central European University1
- Padover, Saul Kussiel1
- Parker, Ralph1
- Patera, Rudolf1
- Plekhanov, Georgiĭ Valentinovich1
- Pravda1
- Radio Free Europe and Radio Liberty, Inc.1
- Radkey, Oliver H.1
- Rajk, László1
- Romanian Unit1
- Romm, Mikhail1
- Royal Institute of International Affairs1
- Samizdat Archives of Radio Free Europe1
- Schell, Erwin Haskell1
- Schumpeter, Joseph A.1
- Schwartz, Harry1
- Seton-Watson, Hugh1
- Shchepanskii, Vladimir Nikolaevich1
- Shub, Boris1
- Smith, Walter Bedell1