Kallio, Petri. “Historical Phonology from Proto-Finnic to Proto-Livonian”. Eesti ja soome-ugri keeleteaduse ajakiri. Journal of Estonian and Finno-Ugric Linguistics 7, no. 1 (September 14, 2016): 39–65. Accessed March 28, 2024. https://ojs.utlib.ee/index.php/jeful/article/view/jeful.2016.7.1.02.