Yerushalmi Eruvin 4:6 ירושלמי עירובין ד׳:ו׳

MISHNAH: If they were two¹⁴Two people staying on the road over the Sabbath and both sleeping during twilight. and some of the cubits of one were inside the cubits of the other they bring and eat in the middle on condition that one not transfer into the other’s [domain]. If they were three and the middle one absorbed between them, he is permitted with them and they with him but the two outside ones are forbidden one with the other.
Rebbi Simeon says, to what is this similar? To three courtyards open to one another and open to the public domain¹⁵The three courtyards are in one row, and each one has a separate exit to the road. If one of the courtyards had no direct exit to the road it would be an appendix of an other courtyard and forced to have an eruv with the latter. But in the case here the eruvim are voluntary. Since the Yerushalmi does not comment on this Mishnah it must assume that this is practice, against the Babli which states that the majority disagrees with R. Simeon.. If both [outer ones] made an eruv with the middle one, that one is permitted with them and they with it but the two outside ones are forbidden one with the other.

HALAKHAH: Paragraph. “If they were two, and some of the cubits of one,” etc. Even though Rebbi Ḥananiah ben Antigonos disagrees with the rabbis about the cubits he agrees with them here about the environs of towns⁸⁰While the quote is from Mishnah 6, the reference is to Mishnah 9 but its original place must have been in the discussion of Mishnah 5:1, which is referred to as “here”. Only for a single person does R. Ḥanina ben Antigonos define a Sabbath domain as circular; for villages and towns he agrees that it is rectangular..