Manava Dharmashastra 1.88

Manvarthamuktāvalī 1.88

adhyāpanādīnāmiha sṛṣṭiprakaraṇe sṛṣṭiviśeṣatayābhidhānaṃ vidhisteṣāmuttaratra bhaviṣyati| adhyāpanādīni ṣaṭ karmāṇi brāhmaṇānāṃ kalpitavān |