Mahabharata 13.94.39

स गत्वाहवनीयेऽग्नौ तीव्रं नियममास्थितःजुहाव संस्कृतां मन्त्रैरेकैकामाहुतिं नृपः

sa gatvāhavanīye'gnau tīvraṃ niyamamāsthitaḥjuhāva saṃskṛtāṃ mantrairekaikāmāhutiṃ nṛpaḥ

Our plain-language meaning of this verse is waiting for scholar review.