Matsyapurana 3.41

3.41

tatas tān abravīd brahmā putrān ātmasamudbhavān
prajāḥ sṛjadhvam abhitaḥ sadevāsuramānuṣīḥ //

Brahmâ continued uttering, "Oh! what an enchanting form! oh! what an enchanting form!" in His love for the goddess Sâvitrî, and the latter, after saluting Him, began to circumambulate Him in reverence. Brahmâ fixed his gaze on Sâvitrî and from Her. As she was circumambulating Him, He felt shy of turning His head each time to Her direction, as His Mânasa putras were standing close by. He therefore created four heads, each pointed to a direction, in order that He may see Sâvitrî undisturbed, without having to turn His head each time in course of Her circumambulations. Seeing Brahmâ in such a condition, Satarûpâ went to heaven with the Mânas sons of the Creator, and as she was travelling towards heaven, Brahmâ put on a fifth head right on top which afterwards He covered with His long matted hair. This is how Brahmâ came to have five heads. After this, Brahmâ lost his powers that He had acquired by practising acesticism, owing to His not controlling His mind and falling into the snares of Cupid. Then Brahmâ dispersed His sons, after directing them to carry on the work of Creation.—35-41.