Kozioł, Krzysztof, and Mieczysław Kula. “Witt Rings of Infinite Algebraic Extensions of Global Fields”. Annales Mathematicae Silesianae 12 (September 30, 1998): 131-139. Accessed May 18, 2024. https://www.journals.us.edu.pl/index.php/AMSIL/article/view/14170.