shabbir why you are saying article by pradeep is not duplicate. this article is 100% duplicate from msdn or that article ( I have given a link)
First thing shabbir, you are saying duplicate. But do you know the meaning of duplicate???
This is not at all duplicate ... This is illegal Copied from some author article.
there is very big difference b/w duplicate and Illegal copied.
Duplicate: Author gives his same article to different different sites or magazine. Then those article are called duplicate.
Illegal(Unauthorized) Copied: Without taking any permission from aouthor, copied that article .
If he gave the permission then author name should be same author. Only you can advertize in your site with name of that author.