Yevamot, Chapter Fourteen, Mishnah Two
Our mishnah contains a debate about which type of deaf woman may be divorced.
Rabbi Nehunia ben Gudgada testified concerning a deaf-mute whose father had given her in marriage, that she could be sent away with a bill of divorcement;
They said to him: the other also is similar to her.
According to Rabbi Nehunia ben Gudgada a deaf minor who was married off by her father can be divorced against her will. In this case, although the marriage is deoraita (because it was arranged by the father), since a woman can be divorced against her will, she can still be divorced when she cannot express her will.
The rabbis take this halakhah one step further, and state that even a woman who married herself off when of sound senses, can still be divorced should she go deaf.
Note that we learned this law in the previous mishnah. The reason that it is restated is that it is a response to Rabbi Nehunian ben Gudgadas testimony, which was also brought in Eduyot 7:9.