Rashi: "Zekeinecha" implies the Great Sanhedrin - the choice of your elders. ¹

Targum Yonasan: "Zekeinecha" implies two Chachamim, and "Shoftecha" three Dayanim (from the Sanhedrin), making five in all [who must go to measure].

Sanhedrin 14a #1 (according to R. Yehudah): 'Zekenecha' implies two Dayanim, and 'Shoftecha' ² two. And we add a fifth Dayan to make an odd number. ³

Sanhedrin 14a #2 (according to R. Eliezer ben Ya'akov): "Zekenecha" refers to the Sanhedrin ha'Gadol and "Shoftecha", to the king ⁴ and the Kohen Gadol. ⁵ - all of whom must go out to where the murdered man is lying.

Sotah, 44b: It implies that the Zekenim must go out personally and not send their Sheluchim. ¹

Yerushalmi Sanhedrin, 8:5: It implies that a lame person is not eligible to sit on the Sanhedrin. ²

Rashi: From the corpse ¹ to the surrounding towns in all directions, to determinee which is the nearest town. ²

Ba'al ha'Turim: They measure from the head. ¹

Sotah 45b #1 (according to R. Eliezer): They measure from the navel. ²

Sotah 45b #2 (according to R. Akiva): They measure from the nose. ³

Sotah 45b #3 (according to R. Eliezer ben Ya'akov): They measure from the neck (where he became a corpse - Rosh in Pasuk 9).

Refer to 21:2:5:1:

Sifri: It implies that they must measure from the corpse to he towns and not vice-versa.

Sotah, 45a: "u'Mad'du el he'Arim" implies that it is a Mitzvah to measure, irrespective of whether they know which town is the closest or not.

Yerushalmi Sotah, 9:2: Then the two towns bring one Eglah Arufah between them and they stipulate that it covers the town to which it was actually the nearest. ¹