Madden, R. H., Guerrero, J., Kay, R. F., Flynn, J. J., Swisher III, C. C., & Walton, A. H. (1997). The Laventan Stage and Laventan Age: New chronostratigraphic and geochronologic units for the Miocene of South America. In R. F. Kay, R. H. Madden, R. L. Cifelli, & J. J. Flynn (Eds.), Vertebrate Paleontology in the Neotropics. (pp. 499–519). Washington, D. C.: Smithsonian Institution Press.

Madden, R. H., J. Guerrero, R. F. Kay, J. J. Flynn, C. C. Swisher III, and A. H. Walton. “The Laventan Stage and Laventan Age: New chronostratigraphic and geochronologic units for the Miocene of South America.” In Vertebrate Paleontology in the Neotropics., edited by R. F. Kay, R. H. Madden, R. L. Cifelli, and J. J. Flynn, 499–519. Washington, D. C.: Smithsonian Institution Press, 1997.

Madden RH, Guerrero J, Kay RF, Flynn JJ, Swisher III CC, Walton AH. The Laventan Stage and Laventan Age: New chronostratigraphic and geochronologic units for the Miocene of South America. In: Kay RF, Madden RH, Cifelli RL, Flynn JJ, editors. Vertebrate Paleontology in the Neotropics. Washington, D. C.: Smithsonian Institution Press; 1997. p. 499–519.

Madden, R. H., et al. “The Laventan Stage and Laventan Age: New chronostratigraphic and geochronologic units for the Miocene of South America.” Vertebrate Paleontology in the Neotropics., edited by R. F. Kay et al., Smithsonian Institution Press, 1997, pp. 499–519.

Madden RH, Guerrero J, Kay RF, Flynn JJ, Swisher III CC, Walton AH. The Laventan Stage and Laventan Age: New chronostratigraphic and geochronologic units for the Miocene of South America. In: Kay RF, Madden RH, Cifelli RL, Flynn JJ, editors. Vertebrate Paleontology in the Neotropics. Washington, D. C.: Smithsonian Institution Press; 1997. p. 499–519.