Markandeyapurana 50.6

50.6

nava brahmāṇa ityete purāṇe niścayaṅgatāḥ /
tato 'sṛjat punarbrahmā rudraṃ krodhātmasambhavam //

When all that offspring of him, the wise one, did not increase, he created other mind-born sons like unto himself, viz., Bhṛgu, Pulastya, Pulaha, Kratu, and Aṅgiras, Marīci, Dakṣa, and Atri, and the mind-born Vasiṣṭha[3]—these were the nine sons of Brahmā, they are positively mentioned in the Purāṇas.

Next Brahmā further created Rudra, whose birth was from his soul when it was angry, and Saṅkalpa, and Dharma who was begotten before all the preceding sons.