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There are 798 citations for articles published in NS journal as of April, 2013 based on the statistics from Google Scholar.

ABC chemistry 
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Energy and Power Source
Environmental Impact
European Virtual Institute for Speciation Analysis (EVISA)

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Gale 

General Science Collection

Geneva Foundation for Medical Education and Research (GFMER)

Georgia State University Library (GSU)
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Mlibrary 

National Science and Technology Library (NSTL)
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Poland Ministry of Science and Higher Education 
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