- Ohloblyn, Oleksander1
- Open Society Archives at Central European University1
- Oppenheimer, J. Robert1
- Orbán, Sándor1
- Osʹmachka, Todosʹ1
- Phillips, Morgan1
- Pilat, Oliver Ramsay1
- Pisky, Fred S.1
- Plamenatz, John Petrov1
- Polish Unit of RFE/RL Research Institute; RFE/RL RI1
- Riefenstahl, Leni1
- Riesman, David1
- Romanian Unit1
- Roosevelt, Eleanor1
- Russell, Bertrand1
- Rákosi, Mátyás1
- Salgado, Plinio1
- Samizdat Archives of Radio Free Europe1
- Schmemann, Alexander1
- Serafimovich, A.1