Väizene, Vivika; Valgma, Ingo; Reinsalu, Enno; Roots, Raul (10–13 June 2013). Analyses of Estonian oil shale resources. International Oil Shale Symposium. Tallinn, Estonia. Archived from the original on 25 January 2015. Retrieved 1 June 2014.
Sepp, Mait (2009). "Piiludes põlevkivitööstuse hälli" [Peeking into the cradle of oil shale industry]. Eesti Loodus (in Estonian) (11). Archived from the original on 6 December 2014. Retrieved 6 December 2014.
Sepp, Mait (2009). "Põlevkivisaaga Narva karjääri maadel" [The oil shale saga on the lands of Narva open-pit mine]. Eesti Loodus (in Estonian) (6). Archived from the original on 13 April 2014. Retrieved 12 April 2014.
egk.ee
Suuroja, Kalle; Mardim, Tiit; Vahtra, Tiina; Ploom, Kuldev; All, Tarmo; Veski, Anu; Kõiv, Maarika; Otsmaa, Merle (2008). "Kohtla-Järve. Seletuskiri" [Kohtla-Järve. Explanation to the maps] (PDF). Eesti Geoloogiakeskus. Geological base map of Estonia (in Estonian). pp. 11–12. Archived from the original(PDF) on 13 December 2014. Retrieved 12 December 2014.
Koel, Mihkel (1999). "Estonian oil shale". Oil Shale. A Scientific-Technical Journal (Extra). ISSN0208-189X. Archived from the original on 9 November 2014. Retrieved 25 October 2008.
"Direct Combustion of Oil Shale"(PDF). Pace Synthetic Fuels Report. 19 (1). The Pace Company Consultants & Engineers: 2-2. March 1982. Retrieved 26 June 2021.
Gamzejev, Erik (1 February 2013). "Ojamaa kaevandus hakkas täie hooga tööle" [The Ojamaa mine began working in full swing]. Põhjarannik (in Estonian). Archived from the original on 22 October 2013. Retrieved 6 December 2014.
Allix, Pierre; Burnham, Alan K. (1 December 2010). "Coaxing Oil from Shale". Oilfield Review. 22 (4). Schlumberger: 6. Archived from the original on 6 January 2015. Retrieved 18 April 2012.
Lindquist, W. (11 September 1937). "Estländska oljeskifferindustrien" [Estonian oil shale industry]. Teknisk Tidskrift. Kemi (in Swedish) (9): 71–75. Archived from the original on 23 July 2014. Retrieved 31 March 2014.
Saarnak et al. (2014), p. 66 Saarnak, Martin; Uibopuu, Lembit; Valgma, Ingo; Nurme, Martin; Väizene, Vivika (2014). "6. Eesti põlevkivi kaevandamisviisid" [6. Mining methods of Estonian oil shale] (PDF). In Valgma, Ingo (ed.). Mäendus [Mining] (in Estonian). Institute of Mining. Tallinn University of Technology. pp. 55–68. ISBN978-9949-430-80-2.
Koel, Mihkel (1999). "Estonian oil shale". Oil Shale. A Scientific-Technical Journal (Extra). ISSN0208-189X. Archived from the original on 9 November 2014. Retrieved 25 October 2008.
Väizene, Vivika; Valgma, Ingo; Reinsalu, Enno; Roots, Raul (10–13 June 2013). Analyses of Estonian oil shale resources. International Oil Shale Symposium. Tallinn, Estonia. Archived from the original on 25 January 2015. Retrieved 1 June 2014.
Sepp, Mait (2009). "Piiludes põlevkivitööstuse hälli" [Peeking into the cradle of oil shale industry]. Eesti Loodus (in Estonian) (11). Archived from the original on 6 December 2014. Retrieved 6 December 2014.
Suuroja, Kalle; Mardim, Tiit; Vahtra, Tiina; Ploom, Kuldev; All, Tarmo; Veski, Anu; Kõiv, Maarika; Otsmaa, Merle (2008). "Kohtla-Järve. Seletuskiri" [Kohtla-Järve. Explanation to the maps] (PDF). Eesti Geoloogiakeskus. Geological base map of Estonia (in Estonian). pp. 11–12. Archived from the original(PDF) on 13 December 2014. Retrieved 12 December 2014.
Lindquist, W. (11 September 1937). "Estländska oljeskifferindustrien" [Estonian oil shale industry]. Teknisk Tidskrift. Kemi (in Swedish) (9): 71–75. Archived from the original on 23 July 2014. Retrieved 31 March 2014.
Sepp, Mait (2009). "Põlevkivisaaga Narva karjääri maadel" [The oil shale saga on the lands of Narva open-pit mine]. Eesti Loodus (in Estonian) (6). Archived from the original on 13 April 2014. Retrieved 12 April 2014.
Allix, Pierre; Burnham, Alan K. (1 December 2010). "Coaxing Oil from Shale". Oilfield Review. 22 (4). Schlumberger: 6. Archived from the original on 6 January 2015. Retrieved 18 April 2012.
Gamzejev, Erik (1 February 2013). "Ojamaa kaevandus hakkas täie hooga tööle" [The Ojamaa mine began working in full swing]. Põhjarannik (in Estonian). Archived from the original on 22 October 2013. Retrieved 6 December 2014.
Koel, Mihkel (1999). "Estonian oil shale". Oil Shale. A Scientific-Technical Journal (Extra). ISSN0208-189X. Archived from the original on 9 November 2014. Retrieved 25 October 2008.