Gobhilagrihyasutra 4.10.1

4.10.1

uttarato gāṃ baddhvo 'patiṣṭherann arhaṇā putra uvāsa (?) se 'ti.

To the north of the place (in which the Arghya reception will be offered to a guest), they should bind a cow (to a post or the like), and should (reverentially) approach it with (the verse), 'Arhanâ putra vâsa' (MB. II, 8, 1).