G. Chartrand, L. Eroh, M.A. Johnson, and O.R. Oellermann, Resolvability in graphs and the metric dimension of a graph, Discrete Appl. Math. 105 (2000), no. 1-3, 99–113.
 F. Harary and R.A. Melter, On the metric dimension of a graph, Ars Combin. 2 (1976), 191–195.
 S.T. Hedetniemi, R.C. Laskar, and H.M. Mulder, New resolvability parameters of graphs, submitted.
 P.J. Slater, Leaves of trees, Congr. Numer. 14 (1975), 549–559.