Reference for Menachot 103:17

והדר אמר רבא הני נמי טיבותין היא אמר קרא (ויקרא ו, יג) סלת מנחה תמיד הרי היא לך כמנחת תמידין

R'Hiyya B'Abba said that R'Johanan had raised the question: Does it mean a whole tenth in the morning and a whole tenth in the evening, or a whole tenth in the morning and in the evening it was dispensed with? - Come and hear, said Raba, for we have learnt: The eighth bore the [High Priest's] meal-offering.<span class="x" onmousemove="('comment',' Tamid 31b, where it is stated that thirteen priests were engaged in the sacrifice of the Daily Offering and all that accompanied it in the morning, and likewise in the evening.');">¹¹</span>

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