כִּֽי־יֵשְׁב֨וּ אַחִ֜ים יַחְדָּ֗ו וּמֵ֨ת אַחַ֤ד מֵהֶם֙ וּבֵ֣ן אֵֽין־ל֔וֹ לֹֽא־תִהְיֶ֧ה אֵֽשֶׁת־הַמֵּ֛ת הַח֖וּצָה לְאִ֣ישׁ זָ֑ר יְבָמָהּ֙ יָבֹ֣א עָלֶ֔יהָ וּלְקָחָ֥הּ ל֛וֹ לְאִשָּׁ֖ה וְיִבְּמָֽהּ׃
If brethren dwell together, and one of them die, and have no child, the wife of the dead shall not be married abroad unto one not of his kin; her husband’s brother shall go in unto her, and take her to him to wife, and perform the duty of a husband’s brother unto her.
Targum Jonathan on Deuteronomy
When brethren from the (same) father inhabit this world at the same time, and have the same inheritance, the wife of one of them, who may have died, shall not go forth into the street to marry a stranger; her brother-in-law shall go to her, and take her to wife, and become her husband.