The Bstan-???gyur contains 224 volumes with 3,626 texts, divided into three major groups: (1) stotras stotras (hymns of praise) in one volume, including 64 texts, (2) commentaries on tantras in 86 volumes, including 3,055 texts, and (3) commentaries on sutras in 137 volumes, including 567 texts.A major development in the history of Tibetan Buddhism occurred in the late 14th or early 15th century,