Śatapatha Brāhmaṇa ("of a hundred paths") 2.6.3.13

2.6.3.13

atha punaḥ prayuñjānasya | pūrvedyuḥ phālgunyai paurṇamāsyai śunāsīryeṇa yajetātha prātarvaiśvadevenātha paurṇamāsenaitadu punaḥ prayuñjānasya

And in the case of one who recommences (the Seasonal offerings),--let him perform the Sunâsîrya on the day preceding the Phâlguna full-moon, and on the following day the Vaisvadeva, and after that the Full-moon offering. This, then, (is the rule) for him who recommences (the Seasonal offerings).