הלכה על במדבר 28:26

The commandment of the additional sacrifice on the day of the festival of Shavouot: That Israel was commanded to sacrifice an additional sacrifice on the day of the festival of Shavouot, as it is stated (Numbers 28:26), "And on the day of the first-fruits when you bring a new meal-offering to the Lord on your festival of Weeks (Shavouot), etc." And I have already written twice that I have spoken about the matter of the additional sacrifices in the Order of Emor el HaKohanim regarding the addition of Pesach (Sefer HaChinukh 299).