Tham khảo Niên_hiệu_Nhật_Bản

Tài liệu tham khảo

WikiPedia: Niên_hiệu_Nhật_Bản http://books.google.com/books?ei=7QY6TbbKOYT58AaIp... http://books.google.com/books?id=18oNAAAAIAAJ&dq=n... //books.google.com/books?id=18oNAAAAIAAJ&pg=PA103 //books.google.com/books?id=18oNAAAAIAAJ&pg=PA106 //books.google.com/books?id=18oNAAAAIAAJ&pg=PA112 //books.google.com/books?id=18oNAAAAIAAJ&pg=PA115 //books.google.com/books?id=18oNAAAAIAAJ&pg=PA121 //books.google.com/books?id=18oNAAAAIAAJ&pg=PA124 //books.google.com/books?id=18oNAAAAIAAJ&pg=PA125 //books.google.com/books?id=18oNAAAAIAAJ&pg=PA129