Reference for Zevachim 16:8

אי הוה כתיב לשלמים וזבח כדקאמרת השתא דכתיב לזבח שלמים לכל דשחיט ליה שלמים להוי

[this teaches that] whatever comes of the flock is to be for a sacrifice of peace-offerings.<span class="x" onmousemove="('comment',' Since a Passover-offering comes of the flock it is included in this deduction. Further, that can only mean after its season, for it has already been deduced supra that if it is offered for anything but itself in its season it is invalid.');">⁶</span>

Jastrow

Jastrow