הלכה על במדבר 29:2

The commandment of the additional sacrifice on the day of Rosh Hashanah: To sacrifice the additional sacrifice on the day of Rosh Hashanah, as it is stated (Leviticus 23:24-25), "On the seventh month on the first of the month, etc. and you shall bring a fire-offering to the Lord, etc." And in the Order of Pinchas (Numbers 29:2-5), it mentions the sacrifice at length. And all of its content is like I wrote about the additional sacrifice of Pesach in the commandment of the additional offering of all of the seven days of Pesach in this Order (Sefer HaChinukh 299).