Menahot, Chapter Ten, Mishnah Two
1) The mitzvah of the omer is that it should be brought from [what grows] near by.
2) If [the crop] near Jerusalem was not yet ripe, it could be brought from any place.
3) It once happened that the omer was brought from Gagot Zerifin and the two loaves from the plain of En Soker.
Section one: It was a mitzvah, meaning it was preferable, for the omer to be brought from barley grown close to Jerusalem.
Section two: However, if this barley was too ripe to be harvested, it could be brought from elsewhere with the land of Israel.
Section three: The mishnah records a time when the barley for the omer had to be brought all the way from Gagot Zerifin, which Albeck identifies as being near Lod (near the Ben-Gurion airport). According to another version of this mishnah, the words are ganot Zerifin which means the fields near Zerifin. The grain used for the two loaves once came from as far away as En Soker, which is near Shechem (in the northern part of Samaria, or the West Bank).