Research Resources
Free www.pdfdrive.com is the largest website for free download of books in PDF format. Claiming over 225 million names.

Free www.base-search.net is one of the most powerful researches on academic studies texts. More than 100 million scientific documents, 70% of them are free

FREE www.science.gov is an American state search engine on 2200+ scientific sites. More than 200 million articles are indexed.

Free www.bioline.org.br is a library of scientific bioscience journals published in developing countries.


Search Engine Gateway www.refseek.com - Academic Resource Search. More than a billion sources: encyclopedia, monographies, magazines.
Paper Clumsy www.worldcat.org - a search for the contents of 20 thousand worldwide libraries. Find out where lies the nearest rare book you need.
Pay https://link.springer.com - access to more than 10 million scientific documents: books, articles, research protocols.
Gateway to various pay sites http://repec.org - volunteers from 102 countries have collected almost 4 million publications on economics and related science.