Bikkurim3: 11
אֵימָתַי אָמְרוּ תּוֹסֶפֶת הַבִּכּוּרִים כַּבִּכּוּרִים? בִּזְמַן שֶׁהִיא בָאָה מִן הָאָרֶץ; וְאִם אֵינָהּ בָּאָה מִן הָאָרֶץ — אֵינָהּ כַּבִּכּוּרִים.
When did they say [that] the supplement to the bikkurim is like the primary bikku-rim? When it comes from the Land; but if it does not come from the Land, it is not like the primary bikkurim.