Linked from
The 76 pages that link to Sanskrit, each with the reason it gives.
SamavedaNarrower topic: The Samaveda's verses and ritual terminology are composed in Vedic Sanskrit.
ValmikiNarrower topic: The Ramayana attributed to Valmiki is composed in Sanskrit.
Sanskrit manuscriptNarrower topic: The manuscripts preserve works composed in this language.
BhavabhutiNarrower topic: Bhavabhuti composed his dramas in this language.