Srimad-Bhagavatam: Canto 9 - Chapter 1 - Verse 27-28
Sanskrit:
शापान्मैथुनरुद्धस्य पाण्डो: कुन्त्यां महारथा: ।जाता धर्मानिलेन्द्रेभ्यो युधिष्ठिरमुखास्त्रय: ॥ २७ ॥नकुल: सहदेवश्च माद्रयां नासत्यदस्रयो: ।द्रौपद्यां पञ्च पञ्चभ्य: पुत्रास्ते पितरोऽभवन् ॥ २८ ॥
ITRANS:
śāpān maithuna-ruddhasyapāṇḍoḥ kuntyāṁ mahā-rathāḥjātā dharmānilendrebhyoyudhiṣṭhira-mukhās trayaḥ
Translation:
Pāṇḍu was restrained from sexual life because of having been cursed by a sage, and therefore his three sons Yudhiṣṭhira, Bhīma and Arjuna were begotten through the womb of his wife, Kuntī, by Dharmarāja, by the demigod controlling the wind, and by the demigod controlling the rain. Pāṇḍu’s second wife, Mādrī, gave birth to Nakula and Sahadeva, who were begotten by the two Aśvinī-kumāras. The five brothers, headed by Yudhiṣṭhira, begot five sons through the womb of Draupadī. These five sons were your uncles.