This is a database record with no hard copy nor even digitized copy, but the record is here to have remember the talk date. There were so many lectures I lost track of the hard copy, Warfield probably used transparencies he had used before or maybe I actually have all the material in some other database record, I just can't remember for sure. It was a good talk, very interesting to the audience. Can't find anything specific to this talk, unless it is the undated transparencies which I found and placed in another database entry with this same title. This talk was given during Warfield's two week period in Mexico when he was giving short course on Generic Design at ITESM, and the documents for one and the other are undoubtedly mixed up.