Improved protocol for the vitrification and warming of rat zygotes by optimizing the warming solution and oocyte donor age - Naomi Nakagata; Satohiro Nakao; Nobuyuki Mikoda; Katsuma Yamaga; Yoshiko Nakagawa; Tetsushi Sakuma; Takashi Yamamoto; Toru Takeo (PLoS ONE, 2025)