%0 Journal Article %T Unavoidable Parallel Minors of 4-Connected Graphs %A Carolyn Chun %A Guoli Ding %A Bogdan Oporowski %A Dirk Vertigan %J Mathematics %D 2006 %I arXiv %X A parallel minor is obtained from a graph by any sequence of edge contractions and parallel edge deletions. We prove that, for any positive integer k, every internally 4-connected graph of sufficiently high order contains a parallel minor isomorphic to a variation of K_{4,k} with a complete graph on the vertices of degree k, the k-partition triple fan with a complete graph on the vertices of degree k, the k-spoke double wheel, the k-spoke double wheel with axle, the (2k+1)-rung Mobius zigzag ladder, the (2k)-rung zigzag ladder, or K_k. We also find the unavoidable parallel minors of 1-, 2-, and 3-connected graphs. %U http://arxiv.org/abs/math/0606577v2