Skandapurana 16.23.41

16.23.41

ṣaṣṭhaśca mānuṣaḥ proktaḥ paiśācaḥ saptamaḥ smṛtaḥ ..
aṣṭamo rākṣasaḥ prokto navamo yajña eva ca .. 41 ..

men are declared the sixth, and the piśāca class is taught as seventh; / rākṣasas are proclaimed the eighth, and sacrifices are the ninth;