Matsya Purana 267.26

267.26

tatastvābharaṇaṃ dadyān mahābhūṣāya te namaḥ.
anena vidhinā kṛtvā saptarātraṃ mahotsavam .. 267.25

Then after reciting the mantra “Mahābhūṣāya te namaḥ,” ornaments should be put on Thus after keeping up rejoicings for seven nights, the devotee should get himself sprinkled with the remainder of the Abhiṣeka water—27 28