Bavula, V. V. “Classification of Modules of Dimension $n$ and Multiplicity 1 over the Weyl Algebra $A_n$”.
Ukrains’kyi Matematychnyi Zhurnal 48, no. 5 (May 25, 1996): 579–587. Accessed April 27, 2025.
https://umj.imath.kiev.ua/index.php/umj/article/view/5290.