http://www.loc.gov/mods/v3 http://www.loc.gov/standards/mods/v3/mods-3-2.xsd
Sách hướng dẫn mọi người cách gieo quẻ, đoán quẻ và giải đáp ý nghĩa của mỗi số quẻ cho mọi người theo Nho giáo.