Devibhagavatapurana 11.17.10

11.17.10

yā sandhyā saiva gāyatrī saccidānandarūpiṇī |
bhaktyā tāṃ brāhmaṇo nityaṃ pūjayecca namettataḥ ||

What is Sandhyâ, that is Gâyatrî; there is no difference whatsoever between the two. The two are one and the same. Both are of the nature of Existence, Intelligence and Bliss. The Brâhmanas would daily worship Her and bow down before Her with greatest devotion and reverence. After the Dhyânam, first worship Her with five upachâras or offerings. Thus:--
Om lam prithivyâtmane gandham, arpayâmi namo namah. Om Ham âkâs’âtmane puspam arpayâmi namo namah. Om ram Vahnyâtmane dîpam arpayâmi namo namah. Aum vam amritâtmane naivedyam arpayâmi namo namah. Om yam ram lam vam ham puspânjalim arpayâmi namo namah. Thus worshipping with five upachâras, you must shew Mudrâs to the Devî.