Reference for Sukkah 12:13

ואיבעית אימא דכולי עלמא יש אם למסורת והכא בהא קמיפלגי מ"ס כי אתאי הלכתא לגרע ומ"ס כי אתאי הלכתא להוסיף

And if you wish you can say hat they are unanimous that the traditional Scriptural text is authoritative, but they differ on this principle; one Master holds that the tradition comes to diminish while the other holds that tradition comes and adds to it.

Jastrow