Brihat Parashara Hora Shastra
कर्कटे मध्यमोऽन्त्यश्च वृश्चिकाद्यद्वितीयकौ । मीनेऽन्तिमस्त्रिभागश्च व्यालवर्गाः प्रकीर्तिताः ॥ ४०॥
Serpent Dreshkanas. The 2nd and 3rd Dreshkan in Kark, the initial one in Vrischik and the last one in Meen are designated, as serpent Dreshkanas.
english translation
karkaTe madhyamo'ntyazca vRzcikAdyadvitIyakau । mIne'ntimastribhAgazca vyAlavargAH prakIrtitAH ॥ 40॥
hk transliteration by Sanscript