Covering radius---Survey and recent results
Gérard Cohen, Mark G. Karpovsky, Harold F. Mattson, James R. Schatz · IEEE Transactions on Information Theory · 1985
All known results on covering radius are presented, as well as some new results. There are a number of upper and lower bounds, including asymptotic results, a few exact determinations of covering radius, some extensive relations with other aspects of coding theory through the Reed-Muller codes, and new results on the least covering radius of any linear[n,k]code. There is also a recent result on the complexity of computing the covering radius.