Matsyapurana 22.6

22.6

eṣṭavyā bahavaḥ putrā yadyeko 'pi gayāṃ vrajet
yajeta vāśvamedhena nīlaṃ vā vṛṣamutsṛjet //

It is well to wish for a number of sons, but if even one son goes and performs śrâddha there at Gayâ, or performs the Aśvamedha sacrifice or sets free a black bull, it is more than ample for the satisfaction of the Piṭris. The sacred Vârâṇasî (Benares) which is the abode of Vimaleśvar the giver of Prosperity and Emancipation, is also dear to the Piṭris.—6-7.