Reference for Gittin 8:2
רבה מתרץ לטעמיה ורבא מתרץ לטעמיה רבה מתרץ לטעמיה דכולי עלמא לפי שאין בקיאין לשמה והכא בגזירת מוליך אטו מביא קמיפלגי
Our Mishnah says: THE BEARER OF A GET FROM ONE PROVINCE TO ANOTHER IN FOREIGN PARTS IS REQUIRED TO DECLARE, 'IN MY PRESENCE IT WAS WRITTEN AND IN MY PRESENCE IT WAS SIGNED'; from which we infer that if he takes it from one place to another in the same province 'in foreign parts'. he need not make the declaration. This conforms with the view of Raba but conflicts with that of Rabbah, [does it not]? — No. You must not infer [that if the Get is taken] from one place to another in the same province 'in foreign parts', the declaration is not required. What you have to infer is that if it is taken from one province to another in the Land of Israel the declaration is not required. But this is stated distinctly in the following clause of the Mishnah: THE BEARER OF A GET [FROM ONE PLACE TO ANOTHER] IN THE LAND OF ISRAEL IS NOT REQUIRED TO DECLARE, 'IN MY PRESENCE IT WAS WRITTEN AND IN MY PRESENCE IT WAS SIGNED'! — If I had only that to go by I should say that while this omission does not invalidate the Get retroactively. It is not permissible in the first instance; now I know that this is also the case.