Lower bounds for q -ary codes with large covering radius. Haas, Wolfgang; Halupczok, Immanuel; Schlage-Puchta, Jan-Christoph — 2009 The Electronic Journal of Combinatorics [electronic only]
The structure of maximal zero-sum free sequences Gautami Bhowmik; Immanuel Halupczok; Jan-Christoph Schlage-Puchta — 2010 Acta Arithmetica