I've searched but didn't find any info on how to disable references (or the codelens completely) in the Visual Studio Code, they're quite useless and annoying for me.
Update: in the new settings editor of VSCode, it's as simple as typing codelens in the search and ticking the first checkbox in the results:
For me, the setting that fixed it was:
"editor.codeLens": false
in my user preferences json file.