Shivapurana 6.6.71

Śivapurāṇa (complete text) 6.6.71

catasraḥ praṇidhātavyāḥ pūrvādikramayogataḥ |
hṛtkaṇṭhāṃseṣu nābhau ca kukṣau pṛṣṭhe ca vakṣasi ||