Manusmriti

siva.sh/manusmriti/2/35

चूडाकर्म द्विजातीनां सर्वेषामेव धर्मतः । प्रथमेऽब्दे तृतीये वा कर्तव्यं श्रुतिचोदनात् ॥ ३५ ॥

sanskrit

According to the teaching of the revealed texts, the Kudakarman (tonsure) must be performed, for the sake of spiritual merit, by all twice-born men in the first or third year.

english translation

cUDAkarma dvijAtInAM sarveSAmeva dharmataH | prathame'bde tRtIye vA kartavyaM zruticodanAt || 35 ||

hk transliteration by Sanscript