1. Refutations by matings;Andrews;IEEE Trans. Comput.,1976
2. Note on the existence of most general semi-unifiers;Baaz,1993
3. Decidability of the universal theory of natural numbers with addition and divisibility;Beltyukov,1976
4. On matrices with connections;Bibel;J. Assoc. Comput. Mach.,1981
5. The Classical Decision Problem;Börger,1997