Intro material on hot compatibility and relation to distribution + gradual rollouts.
Paper: Online, Asynchronous Schema Change in F1
Online, Asynchronous Schema Changes in F1 (Rae et al.)
Book: Sources of Power: How People Make Decisions
Sources of Power: How People Make Decisions - recommended by @statik.
Dynamo is easily understandable and a good intro to distributed eventually consisted databases. http://www.read.seas.harvard.edu/~kohler/class/cs239-w08/decandia07dynamo.pdf
Paper: Highly Available Transactions: Virtues and Limitations
Highly Available Transactions: Virtues and Limitations (Bailis et al.) A very recent but excellent paper.
Paper: Crew Resource Management
Crew Resource Management: a Positive Change for the Fire Service Best article-length resource I've been able to find so far, probably can replace the current Wikipedia link.
Raft is an attempt at making a consensus algorithm that is easily understandable(compared with Paxos). https://ramcloud.stanford.edu/wiki/download/attachments/11370504/raft.pdf
Reminded of this while reading Dynamo paper. Basic topic but probably can find a good short post that discusses it.