==Note from Virim== 

 Added refs to AZT mechanism of action as you requested.  I'm also trying to keep a neutral POV in this section - some strong opinions seem to be creeping in.  Sorry about erasing the other refs on my last edit, but they were a different format from the rest of the article.  And if posting a note here isn't the best way to communicate back, please let me know  I'm pretty new to Wikipedia and am trying to learn proper procedures...  Virim