Buddhist sources 

The Gilgit manuscripts, dated approximately to the 6th–8th centuries CE, contain a Buddhist text known as the Pravrajyāvastu. One of its mātṛkās explicitly refers to Brahmins engaged in the study of the four Vedas. The term “Veda” here is not metaphorical or symbolic; the manuscript clearly enumerates the four canonical Vedas—Ṛgveda, Yajurveda, Sāmaveda, and Atharvaveda. These same four Vedas are also explicitly named in the Milindapañha. Taken together, this evidence demonstrates that the Vedas predate Mahāyāna Buddhist literature and confirms the existence of Vedic gurukulas and mānavakas during the 6th–8th centuries CE.

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