However , scholars are confident that the oral transmission of the texts is reliable : they were ceremonial literature where the exact phonetic expression and its preservation were a part of the historic tradition .
No written records from such an early period survive if they ever existed .
Scholars are confident that the oral transmission of the texts is reliable : they were ceremonial literature where the exact phonetic expression and its preservation were a part of the historic tradition .
No written records from such an early period survive if they ever existed .