Reference for Makhshirin 5:2

הַשָּׁט עַל פְּנֵי הַמַּיִם, הַנִּתָּזִין, אֵינָן בְּכִי יֻתַּן. וְאִם נִתְכַּוֵּן לְהַתִּיז עַל חֲבֵרוֹ, הֲרֵי זֶה בְכִי יֻתַּן. הָעוֹשֶׂה צִפּוֹר בַּמַּיִם, הַנִּתָּזִין וְאֶת שֶׁבָּהּ, אֵינָן בְּכִי יֻתַּן:

[If] one is swimming in the water that which splashes out does not achieve <i>BeKhi Yutan</i>. But if he intended to splash his friend, that does achieve <i>BeKhi Yutan</i>. [If] one makes bubbles in the water that which splashes and what is in it do not achieve <i>BeKhi Yutan</i>.

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