Yāska's Nirukta 17.3

17.3

adhunā rūpasamāsaṃ darśayati, - “kalyāṇavarṇarūpaḥ kalyāṇavarṇasyevāsya rūpam” | kalyāṇavarṇaṃ suvarṇam, tasyeva yasya rūpaṃ sa kalyāṇavarṇarūpaḥ | agniranyo vā kaścit || kalyāṇādiśabdān vigrahaprasaktān nirbravīti, - “kalyāṇaṃ kamanīyaṃ bhavati” | prārthyate tat sarvaiṇaiva | “varṇo vṛṇoteḥ” | āvṛṇoti hi sa āśrayam | “rūpaṃ rocateḥ” | taddhi rocate, taddhi rociṣṇu rbhavati || “evaṃ taddhitasamāsānnibrūyāt”-ityupasaṃhāravacanam |