- Carr, Edward Hallett2
- Joll, James2
- Avrich, Paul1
- Berghaus, Günter1
- Boskoitis, Antonis1
- Enyedi, Ildikó1
- Gryazev, Andrey1
- Kropotkin, Petr Alekseevich1
- Kropotkin, Petr Alekseevich, kniaz'1
- Mansion, Damien1
- Marks, Steven G.1
- Open Society Archives at Central European University1
- Radio Free Europe/Radio Liberty Research Institute (RFE/RL Research Institute)1
- Radio Free Europe/Radio Liberty, Inc - Research Institute1
- Woodcock, George1