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If anyone needs Research paper or Books
Please search the following websites,
1) http://gen.lib.rus.ec
2) http://sci-hub.org
3) http://sci-hub.cc
4) http://sci-hub.bz
4) http://search.crossref.org
5) http://booksc.org/
6) http://libgen.io/
7) http://gen.lib.rus.ec/scimag/