Norvik, Miina, Helle Metslang, Karl Pajusalu, and Eva Saar. “Livonian Polar Questions in Their Areal Context”. Eesti ja soome-ugri keeleteaduse ajakiri. Journal of Estonian and Finno-Ugric Linguistics 13, no. 1 (September 5, 2022): 121–155. Accessed March 28, 2024. https://ojs.utlib.ee/index.php/jeful/article/view/jeful.2022.13.1.05.