This study makes a comparative examination of two parallel volumes in mainstay books of the Shitennoji School: "Bukekishu" of Shokishu and "Denokushu" of Shomei. Bibliographical study with close analysis of difference in composition and contents in reference to architectural practice of the time has revealed that "Bukekishu" of Shokishu is essentially identical to the original document. "Denokushu" of Shomei incorporated new chapters with the intention of developing the document into a more comprehensive manual of architectural techniques. It has been chronologically determined that "Denokushu" of Shomei was compiled in the mid - seventeenth century or, more precicely, after the 4th year of Shouou.
