Mahabharata 3.163.14

ततोऽहं वचनात्तस्य गिरिमारुह्य शैशिरम्तपोऽतप्यं महाराज मासं मूलफलाशनः

tato'haṃ vacanāttasya girimāruhya śaiśiramtapo'tapyaṃ mahārāja māsaṃ mūlaphalāśanaḥ

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