Deepawali is the one of the main festival of India. It is celebrated because Lord Rama has reached Ayodhya on this day after gaining victory over Ravana (mainly in northern part of India). Deepawali is celebrated on Kaartika Amavasya (darkest new moon night).
This question What is the significance of the festival Diwali? Why is it celebrated? discuss about the significance of Deepawali. But my question is: Which scripture mention Lord Rama reached Ayodhya on Kaartika Amavasya (Deepawali) after 14 years of exile?
And also, is there any scripture which claims Lord Rama has slayed Ravana on Vijayadashami?