Journal of Combinatorial Theory, Series AVolume 102, Issue 2, May 2003, Pages 453-454Author IndexAuthor links open overlay panelShow moreShareCitehttps://doi.org/10.1016/S0097-3165(03)00080-3Get rights and contentUnder an Elsevier user licenseopen archivePrevious article in issueNext article in issueRecommended articlesCited by (0)Copyright © 2003 Published by Elsevier Inc. All rights reserved.