On resolvable Steiner 2-designs and maximal arcs in projective planes
  A combinatorial characterization of resolvable Steiner 2-$(v,k,1)$ designs embeddable as maximal arcs in a projective plane of order $(v-k)/(k-1)$ is proved, and a generalization of a conjecture by Andries Brouwer \cite{Br} is formulated. 
Vladimir D. Tonchev
math.CO