Responsa for Gittin 69:11
ההיא דאתאי לקמיה דרב הונא אמר לה מה אעביד ליך דרב לא מגבי כתובה לארמלתא אמרה ליה מידי הוא טעמא אלא דלמא נקיטנא מידי מכתובתי חי ה' צבאות אם נהניתי מכתובתי כלום אמר רב הונא מודה רב בקופצת
A certain woman appealed to Rabbah son of R. Huna [to enforce payment of her <i>kethubah</i>]. He said to her: What can I do for you seeing that Rab would not enforce payment of a <i>kethubah</i> and my father also would not enforce payment of a <i>kethubah</i> to a widow? She said to him: At least grant me maintenance. He replied: You are not entitled to maintenance either, since Rab Judah has said in the name of Samuel: If a woman claims her <i>kethubah</i> in the <i>Beth din</i>, she has no claim to maintenance.<span class="x" onmousemove="('comment',' V. Keth. 542. ');"><sup>9</sup></span>
Teshuvot Maharam
A. During the period of the Geonim the strict law was adopted that no oath could be dissolved by a scholar if such oath was taken by the pronouncing of the name of God, by the Torah, or by the Ten Commandments.
SOURCES: Cr. 18; Pr. 120, 121, 122; Mord. Sheb. 758; Rashba I, 854. Cf. R. Haim b. Isaac Or Zarua, Responsa, 12; Maharil, Responsa 129; Moses Minz, Responsa 47.