Mahabharata 4.39.14
उत्तराभ्यां च पूर्वाभ्यां फल्गुनीभ्यामहं दिवाजातो हिमवतः पृष्ठे तेन मां फल्गुनं विदुः
uttarābhyāṃ ca pūrvābhyāṃ phalgunībhyāmahaṃ divājāto himavataḥ pṛṣṭhe tena māṃ phalgunaṃ viduḥ
Our plain-language meaning of this verse is waiting for scholar review.
Open in the book