While there isn't a "paper" in the academic sense specifically on a file named eXceed.Gun.Bullet.Children.rar (which is a compressed archive format), Game Overview Vertical-scrolling bullet-hell shooter (Danmaku).
As of January 6, 2023, the eXceed series was delisted from Steam because Nyu Media shut down and was unable to transfer the publishing rights back to the original developer.
Community members on platforms like the Steam Community often shared compressed files containing translation assets to help players understand the story before the official Steam release.