Charak Samhita
पूर्वमध्यापराह्णाश्च रात्र्या यामास्त्रयश्च ये। एषु कालेषु नियता ये रोगास्ते च कालजाः ॥११२॥
during different times of the day, viz. forenoon, mid-day and afternoon and during different hours of the night, viz. pre-midnight, midnight and post mid night. Diseases which as a rule manifest themselves during these times are also known as kalaja diseases.
english translation
pUrvamadhyAparAhNAzca rAtryA yAmAstrayazca ye। eSu kAleSu niyatA ye rogAste ca kAlajAH ॥112॥
hk transliteration by Sanscript