sarva-vedetihāsānāṁ
sāraṁ sāraṁ samuddhṛtam
sarva-veda - of all Vedic literature; itihāsānām - of historical literature; sāram sāram - the essence of the essence; samuddhṛtam - is collected (in Śrīmad-Bhāgavatam).
Śrīmad-Bhāgavatam was collected by the incarnation of God, Vyāsadeva, and it was later taught to his son, Śukadeva Gosvāmī. This is a quotation from Śrīmad-Bhāgavatam (1.3.41).