PacificA: Replication in log-based distributed storage systems
http://research.microsoft.com:8082/pubs/66814/tr-2008-25.pdf
https://www.microsoft.com/en-us/research/wp-content/uploads/2008/02/tr-2008-25.pdf
Viewstamped replication revisited.
ZooKeeper: wait-free coordination for internet-scale systems.
Implementing fault-tolerant services using the state machine approach: a tutorial.
Time, clocks, and the ordering of events in a distributed system