http://www.baanjomyut.com/library_2/the_early_rattanakosin_period/05.html

http://jiab007.wordpress.com/2011/04/01/%E0%B8%9E%E0%B8%B1%E0%B8%92%E0%B8%99%E0%B8%B2%E0%B8%81%E0%B8%B2%E0%B8%A3%E0%B8%97%E0%B8%B2%E0%B8%87%E0%B8%94%E0%B9%89%E0%B8%B2%E0%B8%99%E0%B9%80%E0%B8%A8%E0%B8%A3%E0%B8%A9%E0%B8%90%E0%B8%81%E0%B8%B4/