This cell-pack was presented by Warfield during the workshop he gave in Mexico December 1989. The title of his workshop, as listed in his Vita was: "The Management of Complexity Through Systems Design", ITESM (Instituto Tecnologico y de Estudios Superiores de Monterrey), a workshop presented during the week 11-15 December 1989, Monterrey, Mexico. In 2011, These transparencies were found as printouts in Warfield's papers, accompanied by a copy of his paper titled "A Complexity Metric for High-Level Software Languages" which had been published in IEEE-SMC Proceedings 1987. GMU Library has a copy of the 1987 paper, but does not have copies of these transparencies, at least as far as I know now. r.w.8/26/2011
