Shiva Purana
कपिलश्चासुरिः पञ्चशिखः शाल्वलपूर्वकः ॥ चत्वारो योगिनः पुत्रा भविष्यन्ति समा मम ॥ ३३ ॥
Four sons, all Yogins on a par with me, viz—Kapila, Āsuri, Śālvala and Pañcaśikha will be born of me.
english translation
kapilazcAsuriH paJcazikhaH zAlvalapUrvakaH ॥ catvAro yoginaH putrA bhaviSyanti samA mama ॥ 33 ॥
hk transliteration by Sanscript