sets](http://www.cse.chalmers.se/~coquand/vv.pdf) - main
definitions towards a formalization
+* [hoq](https://github.com/valis/hoq/) - A language based on homotopy
+ type theory with an interval (documentation available
+ [here](https://docs.google.com/viewer?a=v&pid=forums&srcid=MTgzMDE5NzAyNTk5NDUxMjg3MDABMDQ5MTM3MjY5Nzc5MzY3ODYzNjABT3A0QWRIempiZTBKATAuMQEBdjI)).
+
* [A Cubical Approach to Synthetic Homotopy
Theory](http://dlicata.web.wesleyan.edu/pubs/lb15cubicalsynth/lb15cubicalsynth.pdf),
Dan Licata, Guillaume Brunerie.