URLs

• https://www.pixiv.net/users/2036511
• https://www.pixiv.net/stacc/ken_oo
• https://twitter.com/ken_oo
• https://twitter.com/intent/user?user_id=95033850
• https://ja.wikipedia.org/wiki/大塚健_(アニメーター)
• https://anidb.net/creator/127
• https://www.animenewsnetwork.com/encyclopedia/people.php?id=9956
• http://blog.so-net.ne.jp/keno/