Chabad.org — English translation + Rashi
Torah Temimah points to Zevachim 48b (unit 2; single primary locus per emergency Core plan).
E-Daf.com — Zevachim 48b
HebrewBooks / Shas PDF
English: “And he shall slaughter it” — why “it”? It [the animal] in the north, and the slaughterer need not be in the north — rather the receiver of the blood must be in the north.
Northern requirement for kabbalah of chatas — the blood of the nasi’s chatas is received in the northern area of the courtyard.
For the chatas of the nasi, the animal must be positioned in the north, but the slaughterer himself need not stand in the north. The critical northern location is that of the receiver of the blood. This distinction keeps the shechitah valid even when space constraints force the slaughterer slightly outside the northern zone, provided the kabbalah occurs in the north.