Agniveshyagrihyasutra 3.2.6.15

3.2.6.15

etaddhasma vaitadvidvāṃsaḥ pūrva ācāryā evamaṣṭakyāṃ gāmevamakalpayaṃstayā vaite pitṝnatarpayaṃsta enāṃstṛptāḥ prajayā paśubhiratarpayan tato ha pitṛbhirmitramakurvata mitraṃ hyeṣāṃ sarvāṇi bhūtānyāsan \

Knowing this indeed, the ancient teachers thus prepared the cow for the Aṣṭakā; by it they gratified the ancestors; being gratified, they gratified them with offspring and cattle; from that, they made friends with the ancestors, for all beings were their friends.