Reference for Challah 2:2

עֲפַר חוּצָה לָאָרֶץ שֶׁבָּא בִסְפִינָה לָאָרֶץ, חַיֶּבֶת בַּמַּעַשְׂרוֹת וּבַשְּׁבִיעִית. אָמַר רַבִּי יְהוּדָה, אֵימָתַי, בִּזְמַן שֶׁהַסְּפִינָה גוֹשֶׁשֶׁת. עִסָּה שֶׁנִּלּוֹשָׁה בְמֵי פֵרוֹת, חַיֶּבֶת בַּחַלָּה, וְנֶאֱכֶלֶת בְּיָדַיִם מְסוֹאָבוֹת:

If earth from outside the Land came to the Land on a boat, the [produce grown from that earth] is subject to the laws of <i>Ma'aserot</i> [tithes] and the Sabbatical year. Rabbi Yehuda says, when is the time from which this applies? When the boat touches the ground. Dough which has been kneaded with fruit juice is obligated in <i>Challah</i>, and it may be eaten with unwashed hands.

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