SQL AlwaysOn References

update : APR 2018
Finding root cause for unexplained Availability Group failover - Trayce Jordan
Troubleshooting Common Scenarios with Always On - MS SQL Tiger Team
MSDN : Failover and Failover Modes (AlwaysOn Availability Groups)
It explain the below scnerio and give example:
-Automatic failover
-Planned manual failover (without data loss)
-Forced failover (with possible data loss)
-Automatic failover set
-Synchronous-commit failover set
-Entire failover set

MSDN : AlwaysOn Availability Groups Troubleshooting and Monitoring Guide
Guideline for troubleshooting some of the common issues in AlwaysOn Availability Groups and monitoring AlwaysOn Availability Groups

Video :
Channel 9 : SQL 2014 Availability Group