“…See [11,29] for details. The homology of special families of set-theoretic Yang-Baxter operators, known as racks and quandles, has been extensively studied, see [4,7,18,20,21,25,26,31], but other than for racks and quandles little is known. Therefore, it is important for the study of invariants of knotted objects to determine settheoretic Yang-Baxter (co)homology groups of biquandles and find explicit formulae of their cocycles.…”