12"Yūko Nagashima". Hitoshi Doi Seiyuu Database. Retrieved March 25, 2025.
12345678910111213"Yūko Nagashima (visual voices guide)". behindthevoiceactors.com (A green check mark indicates that a role has been confirmed using a screenshot (or collage of screenshots) of a title's list of voice actors and their respective characters found in its credits or other reliable sources of information). Retrieved October 9, 2022.