The main MVA ingredients first appeared in
https://cds.cern.ch/record/1429931
That should be contrasted with the pre-MVA analysis described in
http://cds.cern.ch/record/1422388
The most recent results, that mostly reflect some things we learned about visualising things, can be found at
http://cms-results.web.cern.ch/cms-results/public-results/preliminary-results/HIG-16-040/index.html