Rashi on Numbers 3:32/רש"י על במדבר ג׳:ל״ב

1ונשיא נשיאי הלוי AND [ELAZAR THE SON OF AARON THE PRIEST WAS] THE PRINCE OVER THE PRINCES OF THE LEVITES — i.e. he was appointed over all of them. And in regard to what was his overship?

2פקדת שמרי משמרת THE OVERSIGHT OF THEM THAT KEEP THE CHARGE [OF THE SANCTUARY] — i.e. by him was the appointment of all of these.