Cancellation among finite unary algebras
\textit{L. Lovász} showed [Acta Math. Acad. Sci. Hung. 18, 321-328 (1967; Zbl 0174.01401)] that every finite algebra having a one-element subalgebra is cancellable among finite algebras. The present authors prove the converse for finite unary algebras.
scientific article; zbMATH DE number 955093