Anandakanda 1.24.76

1.24.76

tilaparṇīrasenaiva gandhakaṃ bhāvayettataḥ /
saptavārāṃstu deveśi chāyāśuṣkaṃ punaḥpunaḥ //

Then one should impregnate the sulphur with the juice of tilaparṇī / seven times, O ruler of the gods, drying it in the shade again and again.