Looking for logging into the Oauth site and are not getting the correct working link for it? In such a case, you can use the links given here by searching your desired login page in the search box. If the page is present on our website then you will get all the links related to the Oauth site. After that you can login as usual with your login credentials.
https://www.eisbahn.jp/yoichiro/2016/03/social_login.html
https://dev.classmethod.jp/architecture/deep-think-about-oauth-authentication/
https://ja.wikipedia.org/wiki/OAuth
https://qiita.com/TakahikoKawasaki/items/e37caf50776e00e733be
https://www.sakimura.org/2012/02/1487/
https://developer.salesforce.com/docs/atlas.ja-jp.api_rest.meta/api_rest/intro_understanding_web_server_oauth_flow.htm
https://help.salesforce.com/HTViewHelpDoc?id=remoteaccess_authenticate.htm&language=ja
https://boxil.jp/mag/a3207/
https://developers.google.com/youtube/v3/guides/authentication?hl=ja
https://oauth.jp/blog/2016/02/25/oauth-authentication/
https://murashun.jp/blog/20150920-01.html
https://ja.developer.box.com/docs/authenticate-with-oauth-2
https://ja.wordpress.org/plugins/oauth-client/