Sarah Spence Adams Jonathan Cass Matthew Tesch Denise Sakai Troxell Cody Wheeland The minimum span of L(2, 1)-labelings of certain generalized Petersen graphs. 1314-1325 2007 155 Discrete Applied Mathematics 10 http://dx.doi.org/10.1016/j.dam.2006.12.001 db/journals/dam/dam155.html#AdamsCTTW07