On the other hand, Yoshihiro NAKAYAMA says Rinnojinomiya ascended the throne and he was called the Emperor Tobu, and era name became 'Enju' in the year of his enthronement.
これに対し、中山吉弘は輪王寺宮は即位して東武天皇と通称されて、年号は「延寿元年」だったという。