https://cdnjs.cloudflare.com/ajax/libs/jquery/3.4.1/jquery.min.js
https://cdnjs.cloudflare.com/ajax/libs/d3/5.12.0/d3.min.js
https://cdnjs.cloudflare.com/ajax/libs/crossfilter2/1.4.7/crossfilter.min.js
https://cdnjs.cloudflare.com/ajax/libs/dc/3.1.5/dc.min.js