On the choice number of complete multipartite graphs with part size four

H. A. Kierstead, Andrew Salmon, Ran Wang

Let $\mathrm{ch}(G)$ denote the choice number of a graph $G$, and let $K_{s\ast k}$ be the complete $k$-partite graph with $s$ vertices in each part. Erdős, Rubin, and Taylor showed th…