Shivapurana 1.25.58

Śivapurāṇa (complete text) 1.25.58

rudrākṣeṇa japanmantraṃ puṇyaṃ koṭiguṇaṃ bhavet |
daśakoṭiguṇaṃ puṇyaṃ dhāraṇāllabhate naraḥ ||