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Keller, G., T. Adatte, A. Juez, and J. Lopez-Oliva. (2009) 2009. “New Evidence Concerning the Age and Biotic Effects of the Chicxulub Impact in NE Mexico”. Journal of the Geological Society 166 (3): 393-411. doi:10.1144/0016-76492008-116.

Keller, G., J. Lopez-Oliva, W. Stinnesbeck, and T. Adatte. 1997. “Age, Stratigraphy, and Deposition of Near-K T Siliciclastic Deposits in Mexico: Relation to Bolide Impact?”. Geological Society of America Bulletin 109: 410-28. doi:10.1130/0016-7606(1997)109<0410:ASADON>2.3.CO;2.