The Compendium of Bheḷa 1.22.18

1.22.18

prakīrya tāni śayane kalbalenāvaguṇṭhitam | svabhyaktaṃ śāyayejjantuṃ svedaṃ prastaramādiśet ||

Having scattered them on a bed, one should have the well-anointed patient lie down / covered with a blanket; one should designate this as stone-slab sudation.