Reference for Tahorot 5:6

שְׁנֵי כִכָּרִים, אֶחָד טָמֵא וְאֶחָד טָהוֹר, אָכַל אֶת אַחַד מֵהֶם וְעָשָׂה טָהֳרוֹת וּבָא חֲבֵרוֹ וְאָכַל אֶת הַשֵּׁנִי וְעָשָׂה טָהֳרוֹת, רַבִּי יְהוּדָה אוֹמֵר, אִם נִשְׁאֲלוּ זֶה בִפְנֵי עַצְמוֹ וְזֶה בִפְנֵי עַצְמוֹ, טְהוֹרִין. וְאִם נִשְׁאֲלוּ שְׁנֵיהֶן כְּאַחַת, טְמֵאִים. רַבִּי יוֹסֵי אוֹמֵר, בֵּין כָּךְ וּבֵין כָּךְ, טְמֵאִים:

Two loaves of bread, one impure and one pure, if someone ate one of them and then prepared pure things, and then his fellow came and ate the second one and then prepared pure things, Rabbi Yehuda says: If each one of them inquired individually [regarding his own purity status], they are both pure, but if they inquired together, they are impure. Rabbi Yose says: in either case they are impure.

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