Reference for Bekhorot 68:4

וחכ"א

But the Sages say: [In order for him to be clean], either [the second plague] must break out all over his flesh,<span class="x" onmousemove="('comment',' Scripture saying: If the leprosy have covered all the flesh, he shall pronounce him clean. Lev. XIII. 13.');">²</span>

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