Reference for Makkot 30:4

במאי קא מיפלגי בהתראת ספק קא מיפלגי מר סבר התראת ספק שמה התראה

In what aspect are they [Rebbi Yochanon and Reish lakash] arguing in? They are arguing in [the validity of] an uncertain warning. One opinion holds that an uncertain warning is a valid warning. And the other opinion holds that

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