Reference for Ketubot 2:9
הָאִשָּׁה שֶׁנֶּחְבְּשָׁה בִידֵי גוֹיִם עַל יְדֵי מָמוֹן, מֻתֶּרֶת לְבַעְלָהּ. עַל יְדֵי נְפָשׁוֹת, אֲסוּרָה לְבַעְלָהּ. עִיר שֶׁכְּבָשָׁהּ כַּרְכּוֹם, כָּל כֹּהֲנוֹת שֶׁנִּמְצְאוּ בְתוֹכָהּ, פְּסוּלוֹת. וְאִם יֵשׁ לָהֶן עֵדִים, אֲפִלּוּ עֶבֶד, אֲפִלּוּ שִׁפְחָה, הֲרֵי אֵלּוּ נֶאֱמָנִין. וְאֵין נֶאֱמָן אָדָם עַל יְדֵי עַצְמוֹ. אָמַר רַבִּי זְכַרְיָה בֶן הַקַּצָּב, הַמָּעוֹן הַזֶּה, לֹא זָזָה יָדָהּ מִתּוֹךְ יָדִי מִשָּׁעָה שֶׁנִּכְנְסוּ גוֹיִם לִירוּשָׁלַיִם וְעַד שֶׁיָּצָאוּ. אָמְרוּ לוֹ, אֵין אָדָם מֵעִיד עַל יְדֵי עַצְמוֹ:
If a woman were imprisoned by gentiles — if because of money, she is permitted to her husband, [for out of fear of losing their money, they will not be wanton with her. And this is so only when Israel has the upper hand over the idolators. In that instance she is permitted to her husband, even if he is a Cohein. (This instance is not similar to that of a captive woman; for in this instance they are afraid of losing their money.) But if the idolators have the upper hand, even (if she were imprisoned) because of money, she is forbidden to her husband if he is a Cohein. And if her husband is an Israelite, she is permitted in any event. For the wife of an Israelite who was forced is permitted to her husband]; if (she were imprisoned) because of "life," [having been sentenced to death], she is forbidden to her husband [even if he were an Israelite; for we fear that she may have cohabited voluntarily with one of them (to save her life).] If karkom (besiegers) captured a city, [the targum of "matzor" (siege) is "karkuma"], all women married to Cohanim, who are found therein are unfit [forbidden to the priesthood; for the wife of a Cohein is forbidden when she is forced. And if there is in the city one hiding place, where one woman could hide, each of the women of the city is believed to say: I hid in the hiding place and I was not defiled. And since she is believed to say: I hid, she is also believed to say: I did not hide, but I was not defiled.] And if there are witnesses for them — even a bondsman, even a bondswoman — they are believed. And a man is not believed (to testify) for himself. R. Zechariah b. Hakatzav said: [I swear by] "this abode!" (the Temple), "her hand did not leave my hand from the time the gentiles entered Jerusalem until they left" — whereupon they said to him: "A man does not testify for himself." [and if a man testified about a captive woman that she is clean, he may not marry her if he is a Cohein because of suspicion (of false testimony). And if he redeemed her from captivity with his money, he may testify for her and marry her; for one does not "throw away" his money for nothing. If he did not know that she was clean, he would not have given his money for her.]