A notice by the obligee to assign its rights shall not be revoked, unless such revocation is consented to by the assigne文章结合作者自身实践,论述了在债权转让中,债权人未履行通知债务人的义务,但事后经受让人书面通知,债务人签字确认的,只要受让人能够证明转让行为确实存在,该转让并非对债务人绝对无效。