Battle of Tonomoto
- Chôsokabe Kunichika & Chôsokabe Motochika vs. Motoyama Shigetoki
In the 5th month of 1560, Chôsokabe Kunichika captured Nagahama castle from the Motoyama clan. In response to this, Motoyama Shigetoki departed Asakura castle with 2,500 men to take the castle back. Kunichika intercepted him with 1,000 troops near Nagahama castle. This battle is noted for being Chôsokabe Motochika's first battle, in which he fought bravely, greatly impressing his father and his retainers. Shigetoki was completely routed and fled to Urado castle, where Kunichika held him in siege until he was forced to withdraw due to illness.
- Jinbutsu Tanbô・Nihon no Rekishi V.5, Sengoku no Bushô (人物探訪・日本の歴史（５）戦国の武将) Tokyo, Japan, 1982.
- Yamamoto, Takeshi. Chôsokabe Motochika (長宗我部元親) Japan, 1960