Manusmriti

siva.sh/manusmriti/1/66

पित्र्ये रात्र्यहनी मासः प्रविभागस्तु पक्षयोः । कर्मचेष्टास्वहः कृष्णः शुक्लः स्वप्नाय शर्वरी ॥ ६६ ॥

sanskrit

A month is a day and a night of the manes, but the division is according to fortnights. The dark (fortnight) is their day for active exertion, the bright (fortnight) their night for sleep.

english translation

pitrye rAtryahanI mAsaH pravibhAgastu pakSayoH | karmaceSTAsvahaH kRSNaH zuklaH svapnAya zarvarI || 66 ||

hk transliteration by Sanscript