Samvartta Smriti 38

38

vipro daśāhamāsīta dānādhyayanavarjitaḥ
kṣattriyo dvādaśāhena vaiśyaḥ pañcadaśaiva tu
śūdraḥ śudhyati māsena samvartta vacanaṃ yathā

A Brahmin should remain for ten days abstaining from gift-giving and study; / a Kshatriya [is purified] in twelve days, a Vaishya in fifteen, / and a Shudra is purified in a month, according to the statement of Saṃvarta.