Ashtangasamgraha 14.45

14.45

bahirmalakaphāsṛgviḍjanmabhedāccaturvidhāḥ |

nāmato viṃśatividhā bāhyāstatrāmṛjodbhavāḥ ||

samaṃ prapīḍyāṅguṣṭhena vasārdreṇānu pūrayet ||

They are of four kinds according to the difference of origin from external dirt, kapha, blood, and feces,
and of twenty varieties by name. Among them, the external ones arise from lack of cleanliness.
Pressing down evenly with the thumb wet with muscle-fat, one should fill it afterwards.