FRIES S. A Chronological Bibliography of Latgalian Printed Texts from the 18th to Early 20th Centuries [Internet]. Rēzekne, Latvia: Rēzeknes Tehnoloģiju akadēmija; 2023 [cited 2024 Nov. 21]. Available from: https://books.rta.lv/index.php/RTA/catalog/book/28