Evidence for shelf acidification during the onset of the Paleocene-Eocene Thermal Maximum - Bralower, Timothy J.; Kump, Lee; Robinson, Marci; Self-Trail, Jean; Lyons, Shelby; Babila, Tali; Ballaron, Edward; Freeman, Katherine; Hajek, Elizabeth; Rush, William; Zachos, James (Paleoceanography and Paleoclimatology, 2019)