Mark L. Blum 
Origins and Development of Pure Land Buddhism [PDF ebook] 
A Study and Translation of Gyonen’s Jodo Homon Genrusho

In this book, Mark Blum offers a critical look at the thought and impact of the late 13th-century Buddhist historian Gyonen (1240-1321) and the emergent Pure Land school of Buddhism founded by Honen (1133-1212). Blum also provides a clear and fully annotated translation of Gyonen’s Jodo homon genrusho, the first history of Pure Land Buddhism.