Mahabharata 1.71.21

व्रतस्य व्रतकालं स यथोक्तं प्रत्यगृह्णतआराधयन्नुपाध्यायं देवयानीं च भारत

vratasya vratakālaṃ sa yathoktaṃ pratyagṛhṇataārādhayannupādhyāyaṃ devayānīṃ ca bhārata

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