佛祖統紀 3.76

3.76

次漸教者有三時。鹿苑漸初。方等漸中。般若漸末。總名為漸教。

Next, the gradual teaching has three periods: the Deer Park is the initial gradual; the Vaipulya is the middle gradual; the Prajñā is the final gradual. They are collectively named the gradual teaching.