“…Since the original work of Montgomery, the case r > 1 has widely been dealt with in the literature for different types of graphs [8,6,7,11,12,14,15,19,22,24], with particular emphasis in the case r = 2 [1,2,3,4,5]. Of particular interest for the topic of this paper, let us remark the studies of Mohanapriya et al [20] and Furmańczyk et al [9] concerning the r-dynamic coloring of different families of helm graphs. In particular, the last mentioned paper deals with the r-dynamic chromatic number of the line graph of a helm graph, which coincides as such with the so-called r-dynamic edge chromatic number of a helm graph.…”