Srimad-Bhagavatam: Canto 8 - Chapter 1 - Verse 50
Sanskrit:
त्रयोदश्यामथो विष्णो: स्नपनं पञ्चकैर्विभो: ।कारयेच्छास्त्रदृष्टेन विधिना विधिकोविदै: ॥ ५० ॥
ITRANS:
trayodaśyām atho viṣṇoḥsnapanaṁ pañcakair vibhoḥkārayec chāstra-dṛṣṭenavidhinā vidhi-kovidaiḥ
Translation:
Thereafter, following the directions of the śāstra with help from brāhmaṇas who know the śāstra, on the thirteenth day of the moon one should bathe Lord Viṣṇu with five substances [milk, yogurt, ghee, sugar and honey].