Albert Barnes Commentary Numbers 28:9-10

"And on the sabbath day two he-lambs a year old without blemish, and two tenth parts [of an ephah] of fine flour for a meal-offering, mingled with oil, and the drink-offering thereof: this is the burnt-offering of every sabbath, besides the continual burnt-offering, and the drink-offering thereof." — Numbers 28:9-10 (ASV)

The Sabbath-offering, not previously enjoined, consisted of two lambs, properly accompanied, in addition to the regular daily offering.