How to write XAPI statements:
https://learningsolutionsmag.com/articles/1526/five-things-a-web-developer-needs-to-know-about-the-xapi
https://www.devlinpeck.com/tutorials/write-xapi-statement
Confusion between JSON and JavaScript Object:
https://medium.com/@alifabdullah/never-confuse-json-and-javascript-object-ever-again-7c32f4c071ad
Context:
https://learningpool.com/xapi-statement-101-context-element/
https://xapi.com/blog/deep-dive-context/
https://trello.com/b/NHz6aCDV/experience-api-xapi-tincan
https://github.com/liris-tweak/csv-to-xapi