Republic of Latvia
State Archives of Latvia,
Center for the Documentation of the Consequences of Totalitarianism of the Constitutional Protection Bureau of the Republic of Latvia,
Archives of the Saeima of the Republic of Latvia,
Latvian Television Archives,
Latvia State Archives of Film, Photography and Audiovisual Documents,
Jelgava History and Art Museum named after G. Eliass,
Museum of Secondary school of Priezmale,
Museum of Literature, Theater, and Music (Latvia),
Popular Front Museum (Latvia),

Republic of Estonia
Estonian Film Archives,
State Archives of Estonia,
Estonian History Museum,

Republic of Lithuania
Lithuanian Special Archives,
Funds of the Archives of the Seimas of the Republic of Lithuania,
Museum of Genocide Victims of the Lithuanian Genocide and Resistance Research Center,
National Museum of Lithuania,

Russian Federation
International Society “Memorial” Russian archives on USSR dissidents,
Russian State Archive of Contemporary History,

Documents of private collections
Arvydas Anušauskas, Vilma Juozavičiūte, Pēteris Korsaks, Pavo Kuiva, Janīna Kursīte, Lidija Lasmane, Olev Livik, Mart Nikluss, Jaroslav Nosek, Jiří Nosek, Helena Noskova, Pēteris Šķiņķis, Guntis Švītiņš, Ritvars Jansons, Ainars Mazvērsītis, Vilens Tolpežņikovs, Raits Valters, Viljar Viljame.