“Biostratigraphy of Guadalupian (Mid­dle Permian) am­mo­noids from the Olinalá For­ma­tion, Southern Mex­i­co”. Carnets Geol. 26 (February 28, 2026): 125–150. Accessed June 6, 2026. https://www.carnetsgeol.net/ojs/CG/article/view/73.