Bhaishajyaratnavali 4.57

Bhaiṣajyaratnāvalī (ed. Rājeśvaradatta Śāstrī) 4.57

dravyapratinidhi-paribhāṣākadācid dravyamekaṃ vā yoge yatra na labhyate
tattadguṇayutaṃ dravyaṃ parivarttena gṛhyate