A solution to a problem of Erdos, Rubin and Taylor is obtained by showing that if a graph G is (a : b)-choosable, and c/d > a/b, then G is not necessarily (c : d)-choosable. Th...
This paper revisits the existence and construction problems for polygonal designs (a special class of partially balanced incomplete block designs associated with regular polygons)...
Gargi Bhattacharyya, John Hegeman, Joohyung Kim, J...