Microsoft Web Browser Federated Sign-on Protocol Specification
Web Services Federation Language
http://specs.xmlsoap.org/ws/2006/12/federation/ws-federation.pdf
Understanding WS-Federation
Overview of ADFS
Microsoft Administering Active Directory Federation Services Guide
OpenSSO, WS-Federation & IBM DataPower by Joachim Andre
https://opensso.dev.java.net/files/documents/3676/79106/OpenSSO-WS-Fed-DataPower-FederationPoC.pdf