Brihat Samhita
ताम्रः कपिलो वाअर्कः शिशिरे हरिकुङ्कुमच्छविश्च मधौ । आपाण्डुकनकवर्णो ग्रीष्मे वर्षासु शुक्लश्च ॥ ३-२३ ॥
If in Śiśira (February, March) the sun be of copper colour or red black, if, in Vasanta (April, May), blue crimson, if, in Grīṣma (June, July), slightly white and of gold color, if, in Varṣā (August, September), white.
english translation
tAmraH kapilo vAarkaH zizire harikuGkumacchavizca madhau । ApANDukanakavarNo grISme varSAsu zuklazca ॥ 3-23 ॥
hk transliteration by Sanscript