What are the earliest books on Taoism and Buddhism?

The first classic of Buddhism is Hua Yan Jing. The first sentence of Hua Yan Jing proves that the first classic spoken by Buddha in this world is Hua Yan Jing.

The first classic of Taoism is Tao Te Ching, and the author of Tao Te Ching is Lao Yong. Taoism believes that it is the old gentleman, that is, the moral god. There are offerings in Sanqing Hall of Taoist Temple.