PERILLI, NICOLA, and LUIS VICTOR DUARTE. “TOARCIAN NANNOBIOHORIZONS FROM LUSITANIAN BASIN (PORTUGAL)AND THEIR CALIBRATION AGAINST AMMONITE ZONES”. RIVISTA ITALIANA DI PALEONTOLOGIA E STRATIGRAFIA 112, no. 3 (November 30, 2006). Accessed June 13, 2025. https://riviste.unimi.it/index.php/RIPS/article/view/6350.