There is also no sign that "Heike Monogatari," "Jokyu-ki," and "Rokudai Shojiki" (A Story of Events of Six Emperors) were used, so it is believed that each historical material (records of battles) which came to be a foundation of the work was each used in its own respective way.
また、『平家物語』や『承久記』、『六代勝事記』も使われた形跡は無く、それぞれの元となった史料（合戦記）をそれぞれの視角で利用したのではないかとする。