These are the references I think pertinent from the bibliography of Cynthia Irwin-Williams [American Antiquity, Vol. 59(4)]:
1967 Comments on Allegations by J.L. Lorenzo Concerning Archaeological Research at Valsequillo, Puebla. Misc. Publications No. 1, Paleoindian Institute, Eastern New Mexico, Portales.
1967 Associations of Early Man with Horse, Camel, and Mastodon at Hueyatlaco, Valsequillo (Puebla, Mexico). In Pleistocene Extinctions: The Search for a Cause, ed. by P.S. Martin and H.E. Wright, Jr. Proceedings of the VII Congress of the International Association of Quaternary Research. Yale Univ. Press.
1969 Comments on the Associations of Archaeological Materials and Extinct Fauna in the Valsequillo Region, Puebla, Mexico. American Antiquity, Vol. 34:82-93.
1969 Artefactos humanos encontrados en asociacion con los restos de une fauna extinta pleistocenica, en las region de Valsequillo, Pueblo, Mexico. In Proceedings of the First Congress on Early Man in Latin America, Universidad de Antofagasta, Chile.
1969 Dilemma Posed by Uranium-Series Dates on Archaeologically Significant Bones from Valsequillos, Puebla, Mexico. Earth and Planetary Science Letters 6:237-244.
1978 Summary of Archaeological Evidence from the Valsequillo Region, Puebla, Mexico. In Cultural Continuity in Mesoamerica, ed. by D.L. Browman. Mouton, The Hague.
Hope this helps. You need to check a major library. But, when doing serious research, that's always the way you have to go.
also, I worked up a bunch of questions as I was reading last night and I'll try to get those to see what you think, know or can recommend.
With regards to C14 dating. I liked the 50s A-bomb testing avenue and know that it would increase the available neutrons which in turn increases C14 concentrations. Im still digging on that subject. Thanks for pointing it out.
Here is where I am also going. What effect, and how would C14 dating be adjusted for sealed underground water reservoirs seepage? Correct me if Im wrong, but the sealed water chamber would be free of C14 because it has been shielded from cosmic radiation. If it were to leech out at, some point, it would upset C14 ratios?
This is a new avenue of thought for me, but there are/were a lot of underground water that move and seep due to tectonic movement throughout the ages?
As usual, you are the field expert and Id love to hear your thoughts.
K4