Revākhaṇḍa ascribed to the Vāyupurāṇa (RKV) 231.16

231.16

aṅgāreśvaratīrthāni tāvantyeva munīśvarāḥ /
sārasvatāni catvāri catvāro dārukeśvarāḥ //

the pilgrimage places of Aṅgāreśvara are just as many, O lords of sages; / four belong to Sarasvatī, and four are Dārukeśvaras;