1. The Burnside Problem and Identities in Groups;Adian,1979
2. A proof of the existence of n-valued asymmetric infinite sequences;Arshon;Mat. Sb. (N.S.),1937
3. Avoidable patterns in strings of symbols;Bean;Pacific J. Math.,1979
4. Graphs and Hypergraphs;Berge,1973
5. Lattice Theory;Birkhoff,1967