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\bibitem{Hildebrand1997} Hildebrand, A. R.,, Pilkington, M. Halpenny, J. F., Cooper, R. V., Connors, M., Ortiz-Aleman, C., Chavez, R. E., Urrutia-Fucugauchi, J., Graniel-Castro, E., Camara-Zi, A., \& Buffler, R. T. (1997). Mapping Chicxulub Crater Structure with Gravity and Seismic Reflection Data (abstract).24--25.

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