SB 9.1.36
evam stritvam anupraptah
sudyumno manavo nrpah
sasmara sa kulacaryam
vasistham iti susruma
Translation by His Divine Grace A. C. Bhaktivedanta Swami Srila Prabhupada:
I heard from reliable sources that King Sudyumna, the son of Manu, having thus achieved femininity, remembered his familial spiritual master, Vasistha.