BaudhDhS, 4, 8, 4.2 viprādi tat kṛtaṃ kena pavitrakriyayānayā //

JB, 1, 232, 1.0 tad āhur yad ekaviṃśam anu sarve yajñakratavaḥ saṃtiṣṭhante 'ty u vā ekaviṃśāny ukthāni rātrir ety atha kenaiṣām ekaviṃśam anu rātriḥ saṃtiṣṭhata iti //

MBh, 13, 109, 5.1 adharmānmucyate kena dharmam āpnoti vai katham /