Padmapurana 6.198.50

The Purāṇa named Śrīmad-Bhāgavata fulfills desires for human beings; / nevertheless, listening to it grants devotion only to one who is without desires.

The wishing tree called Śrīmad-Bhāgavata has the sprout of the syllable Oṃ; its birth is from good people; it has twelve cantos, radiant with devotion [...]

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which arose from the watering trench;