Manusmriti

siva.sh/manusmriti/2/37

ब्रह्मवर्चसकामस्य कार्यो विप्रस्य पञ्चमे । राज्ञो बलार्थिनः षष्ठे वैश्यस्यैहार्थिनोऽष्टमे ॥ ३७ ॥

sanskrit

(The initiation) of a Brahmana who desires proficiency in sacred learning should take place in the fifth (year after conception), (that) of a Kshatriya who wishes to become powerful in the sixth, (and that) of a Vaisya who longs for (success in his) business in the eighth.

english translation

brahmavarcasakAmasya kAryo viprasya paJcame | rAjJo balArthinaH SaSThe vaizyasyaihArthino'STame || 37 ||

hk transliteration by Sanscript