Template:Riccardi et al., 1991
- Riccardi, A.C., Damborenea, S.E., Manceñido, M.O. & Ballent, S.C. 1991. Hettangian and Sinemurian (Lower Jurassic) biostratigraphy of Argentina. Journal of South American Earth Sciences 4(3): 159–170. etal1991 hettangian sinemurian.pdf PDF