Skandapurana 5.220.33

5.220.33

ekādaśapramāṇena tataścānye nṛpottama ..
ajaśca prathamaṃ sṛṣṭaḥ sa tathā medhyatāṃ gataḥ .. 33 ..

Then others [were created], O best of kings, according to a measure of eleven; / and the goat was created first, and thus it attained sacrificial fitness. // 33