1. Graph Products and Covering Graph Imbeddings;Abay-Asmerom,1990
2. Embeddings of bipartite graphs;Abu-Sbeih;J. Graph Theory,1983
3. Thickness of arbitrary complete graphs;Alekseev;Mat. Sbornik,1976
4. Two-fold triple systems and graph imbeddings;Alpert;J. Combinatorial Theory A,1975
5. Components of branched coverings of current graphs;Alpert;J. Combinatorial Theory B,1976