Kaczyński, Tomasz. “Recursive Coboundary Formula for Cycles in Acyclic Chain Complexes”. Topological Methods in Nonlinear Analysis 18, no. 2 (December 1, 2001): 351–371. Accessed July 3, 2024. https://apcz.umk.pl/TMNA/article/view/TMNA.2001.039.