Erratum to "Collapsible biclaw-free graphs": [Discrete Math 306 (2006) 2115-2117]

If G is a 2-connected bipartite biclaw-free graph with (G) 4, then by [2, Lemma 2.2], every edge of G lies in a 4-cycle, and then by Lemma 2.5 (the correct version), G is collapsible. It follows that G will have a spanning eulerian subgraph. Note that a Hamiltonian cycle of G is a spanning eulerian subgraph of G with maximum degree 2. We consider it one possible way to attack Conjecture 1.1 of [2] (originally from [3]). We apologize to the readers for our careless errors.