Prykarpatski, A.K., O.D. Artemovych, Z. Popowicz, and M.V. Pavlov. 2010. “Riemann Type Algebraic Structures and Their Differential-Algebraic Integrability Analysis”. Carpathian Mathematical Publications 2 (1):96-108. https://scijournals.pnu.edu.ua/index.php/cmp/article/view/3996.