Gitin3: 3
הַמֵּבִיא גֵט וְאָבַד הֵימֶנּוּ, מְצָאוֹ לְאַלְתַּר — כָּשֵׁר; וְאִם לָאו — פָּסוּל. מְצָאוֹ בַחֲפִיסָה אוֹ בִדְלֻסְקְמָא, אִם מַכִּירוֹ — כָּשֵׁר.  הַמֵּבִיא גֵט וְהִנִּיחוֹ זָקֵן אוֹ חוֹלֶה — נוֹתְנוֹ לָהּ בְּחֶזְקַת שֶׁהוּא קַיָּם. בַּת יִשְׂרָאֵל הַנְּשׂוּאָה לְכֹהֵן, וְהָלַךְ בַּעְלָהּ לִמְדִינַת הַיָּם — אוֹכֶלֶת בַּתְּרוּמָה בְּחֶזְקַת שֶׁהוּא קַיָּם. הַשּׁוֹלֵחַ חַטָּאתוֹ מִמְּדִינַת הַיָּם — מַקְרִיבִין אוֹתָהּ בְּחֶזְקַת שֶׁהוּא קַיָּם.
[If] one was bringing a get and lost it —- [if] he found it immediately, it is valid; if not, it is void. [If] he found it in a pouch or in a case, [and] he recognizes it, it is valid.  One who brings a get and had left him old or ill may give it to her on the assumption that he is alive. The daughter of a non-Kohen who was married to a Kohen —- and her husband went overseas —- may eat terumah on the assumption that he is alive. [If] one sends his sin-offering from overseas, it may be offered on the assumption that he is alive.