Surya Siddhanta
देवासुराणाम् अन्योन्यम् अहोरात्रम् विपर्ययात् । किम् अथ तत् कथम् वा स्याद् भानोर् भगणपूरणात्॥
For what reason are the day and night of the gods and of the demons opposed to one another? or how does that take place by means of the sun's completion of his revolution?
english translation