Yoshikazu KONDO, an expert on the decorum and records of the past, authenticated the costumes and armor of the three portraits in detail, and claimed that these three portraits could be drawn in the first period of the 13th century.
故実家の近藤好和は、三像の衣装・武具を綿密に考証し、三像の成立が13世紀前期まで遡りうることを示している。