Shiva Purana
यदा नवदिनं प्राणा वहंत्येव त्रिमासकम्॥ मासद्वयं च द्वे मासे दिना द्वादश कीर्तिताः॥ ५५॥
If for nine days, he lives for three months, twice two months, and twelve days (i.e. seven months and twelve days).
english translation
yadA navadinaM prANA vahaMtyeva trimAsakam॥ mAsadvayaM ca dve mAse dinA dvAdaza kIrtitAH॥ 55॥
hk transliteration by Sanscript