Not papers or books, but I'd recommend you look at the blog articles and such that Basho published about their design of Riak. In particular, they wrote a great article explaining vector clocks as opposed to other synchronizing mechanisms, and they wrote several good articles on CRDTs.

https://riak.com/category/technical/ - Riak blog

https://www.allthingsdistributed.com/files/amazon-dynamo-sos... - Dynamo paper that Riak was in part based on