Rannut, Mart (2004). "Language Policy in Estonia"(PDF). Noves SL. Revista de Sociolingüística. Archived from the original(PDF) on 2010-07-03. Retrieved 2009-02-27.
Kallio, Petri (2007). "Kantasuomen konsonanttihistoriaa"(PDF). Mémoires de la Société Finno-Ougrienne (in Finnish). 253: 229–250. ISSN0355-0230. Retrieved 2009-05-28. Note that reconstructed *č and *c stand for affricates [t͡ʃ], [t͡s].
Rannut, Mart (2004). "Language Policy in Estonia"(PDF). Noves SL. Revista de Sociolingüística. Archived from the original(PDF) on 2010-07-03. Retrieved 2009-02-27.
Kallio, Petri (2007). "Kantasuomen konsonanttihistoriaa"(PDF). Mémoires de la Société Finno-Ougrienne (in Finnish). 253: 229–250. ISSN0355-0230. Retrieved 2009-05-28. Note that reconstructed *č and *c stand for affricates [t͡ʃ], [t͡s].