Reference for Pesachim 181:9

ואין עושין חבורת נשים ועבדים וקטנים:

<big><b>MISHNAH: </b></big>ONE MAY NOT SLAUGHTER THE Passover offering FOR A SINGLE PERSON: THIS IS R'JUDAH'S VIEW; BUT R'JOSE PERMITS IT. AND EVEN A COMPANY OF A HUNDRED WHO CANNOT EAT AS MUCH AS AN OLIVE [JOINTLY], ONE MAY NOT KILL FOR THEM.

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