Fixes #13

Updates GTC and NVIDIA blog links, adds GCC link

Author: Jeff Larkin

99-End.markdown

@@ -4,8 +4,9 @@ References
 ==========
 
 * [OpenACC.org](http://openacc.org)
-* [OpenACC on the NVIDIA Parallel Forall Blog](http://devblogs.nvidia.com/parallelforall/tag/openacc/)
+* [OpenACC on the NVIDIA Developer Blog](https://developer.nvidia.com/blog/tag/openacc/)
 * [PGI Insider Newsletter](https://www.pgroup.com/resources/articles.htm)
-* [OpenACC at the NVIDIA GPU Technology Conference](http://bit.ly/gtc-openacc)
+* [OpenACC at the NVIDIA GPU Technology Conference](https://www.nvidia.com/en-us/on-demand/search/?facet.mimetype[]=event%20session&layout=list&page=1&q=OpenACC&sort=date)
 * [OpenACC on Stack Exchange](http://stackoverflow.com/questions/tagged/openacc)
 * [OpenACC Community Slack](https://www.openacc.org/community#slack)
+* [OpenACC on the GCC Wiki](https://gcc.gnu.org/wiki/OpenACC)