Reference for Ketubot 30:2

ואמר רב לא שנו אלא להחיותו אבל ליוחסין לא ושמואל אמר לפקח עליו את הגל

And Rav said: They have taught this only with regard to sustaining it, but not with regard to lineage. And Shmuel said: [They have taught this only] with regard to removing stones from on top of it.

Jastrow

Jastrow