Mbh 1.122.5

“Vaisampayana continued, ‘Thus addressed by Pandu, that subjugator of hostile cities, the handsome Kunti, ever attentive to what was agreeable and beneficial to her lord, then replied unto him, saying, ‘In my girlhood, O lord, I was in my father’s house engaged in attending upon all guests. I used to wait respectfully upon Brahmanas of rigid vows and great ascetic merit. One day I gratified with my attentions that Brahmana whom people call Durvasa, of mind under full control and possessing knowledge of all the mysteries of religion. Pleased with my services, that Brahmana gave me a boon in the form of a mantra (formula of invocation) for calling into my presence any one of the celestials I liked. And the Rishi, addressing me, said, ‘Anyone among the celestials whom thou callest by this shall, O girl, approach thee and be obedient to thy will, whether he liketh it or not. And, O princess, thou shall also have offspring through his grace.’ O Bharata, that Brahmana told me this when I lived in my father’s house. The words uttered by the Brahmana can never be false. The time also hath come when they may yield fruit. Commanded by thee, O royal sage, I can by that mantra summon any of the celestials, so that we may have good children. O foremost of all truthful men, tell me which of the celestials I shall summon. Know that, as regards this matter, I await your commands.’