Calcifications in thyroid tumors on ultrasonography: Calcification types and relationship with histopathological type - Kobayashi, K; Fujimoto, T; Ota, H; Hirokawa, M; Yabuta, T; Masuoka, H; Fukushima, M; Higashiyama, T; Kihara, M; Ito, Y; Miya, A; Miyauchi, A (Ultrasound International Open, 2018)