Managing Editor

annals of discrete mathematics Managing Editor Peter L. HAMMER, University of Waterloo, Ont., Canada Advisory Editors C. BERGE, Universitd de Paris, France M.A. HARRISON, University of California, Berkeley, CA, U.S.A. V. KLEE, University of Washington, Seattle, WA, U.S.A. J.H. VAN LINT, California Institute of Technology, Pasadena, CA, U.S.A. G.-C. ROTA, Massachusetts Institute of Technology, Cambridge, MA, U.S.A.

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