Mahabharata 200.35

न चैषां मैथुनो धर्मो बभूव भरतर्षभ
संकल्पादेव चैतेषामपत्यमुदपद्यत

Na chaisham maithuno dharmo babhuva bharatarshabha
Sankalpadeva chaiteshamapatyamudapadyata