On minimization theorems for polyadic groups H-derived from groups Jacek Michalski — 1991 Beiträge zur Algebra und Geometrie = Contributions to algebra and geometry
Note on polyadic groups on sets with at most 7 elements Kazimierz Glazek; Jacek Michalski — 1987 Beiträge zur Algebra und Geometrie = Contributions to algebra and geometry