Reference for Shabbat 247:1

ידו על כתף חבירו ויד חבירו על כתיפו ותולה ומפשיט

his hand upon his fellow's shoulder, and his fellow's hand [rested] upon his shoulder, and so [the animal] was suspended and skinned.<span class="x" onmousemove="('comment',' But the staves might not be used then. ');">¹</span>

Jastrow