* [[http://habrahabr.ru/post/142925/]] * [[http://jasig.github.io/cas/4.1.x/protocol/OpenID-Protocol.html]] * [[http://wiki.openid.net/w/page/12995226/Run%20your%20own%20identity%20server]] * [[http://openid.net/developers/libraries/]] * [[http://findingscience.com/mod_auth_openid/]]