Brihat Samhita
उक्तविपरीतरूपो न शुभकरो धूमकेतुरुत्पन्नः । इन्द्रायुधानुकारी विशेषतो द्वित्रिचूलो वा ॥ ११-०९ ॥
If it be the opposite of these, or of the shape of the rainbow or with two or three tails, mankind will not be happy.
english translation
uktaviparItarUpo na zubhakaro dhUmaketurutpannaH । indrAyudhAnukArI vizeSato dvitricUlo vA ॥ 11-09 ॥
hk transliteration by Sanscript