Manava Dharmashastra 3.187

3.187

uktārthaḥ prāgevāyaṃ ślokaḥ | somaṃ pibanti jyotiṣṭomādiṣvevatā indrādayaḥ | havirbhujaścarupuroḍāśādidevatāḥ | ājyapā ādhārāvājyabhāgaprayājādidevatāḥ | sukālinaḥ | kālayanti apavarjayanti karmeti 'sukālinaḥ' | karmāpavargahomadevatā "ayāścāgnesyanabhiśastītyādi" vihitāḥ |

Those by name Somapās are the Pitṛs of Brāhmaṇas; the Havirbhujs are the Pitṛs of Kṣatriyas; those by name Ājyapas, of Vaiśyas; and of Śūdras, Sukālins.—(197)

Medhātithi’s commentary (manubhāṣya):
What this verse means has been explained before.

The ‘Somapās’ are those that drink Soma; i.e., Indra and other deities of the Jyotiṣṭoma and other sacrifices.

‘Havirbhujs’—are the deities for cooked rice, cake, &c.

‘Ājyapas’—are the deities for the libations called ‘Āghāra,’ ‘Ājyabhāga,’ ‘Pragāju,’ and so forth.

‘Sukālins’—are those who complete, accomplish, sacrificial rites. The deities conducive to the accomplishment of sacrificial rites are those prescribed in such Mantras as ‘Ayāścāgnesyanabhiśasti, &c., &e.’—(197)