Shapiro's name is on about seven different CRDT papers :) it makes citations difficult for the Wikipedia article. Personal opinion, this[0] 2011 paper is probably the best one to read, where Shapiro's and Baquero's teams finally joined forces and put out a good comprehensive paper on the subject. The one you linked focuses a bit too heavily on TreeDoc in lieu of good treatment of CRDT theory. Their survey of known CRDTs[1] is also worth reading.
[0] https://hal.inria.fr/file/index/docid/609399/filename/RR-768...
[1] https://hal.inria.fr/inria-00555588/document