The official DOI (digital object identifier) link registration agency for scholarly and professional publications. Crossref operates a cross-publisher citation linking system that allows a researcher to click on a reference citation on one publisher’s platform and link directly to the cited content on another publisher’s platform, subject to the target publisher’s access control practices. This citation-linking network covers millions of articles and other content items from several hundred scholarly and professional publishers.
Provides a simple way to search broadly for scholarly literature. Includes peer-reviewed papers, theses, books, abstracts and articles, from academic publishers, professional societies, preprint repositories, universities and other scholarly organizations. Google Scholar sorts articles by weighing the full text of each article, the author, the publication in which the article appears, and how often the article has been cited in other scholarly literature, so that the most relevant results are returned on the first page.
The Index Medicus for the Eastern Mediterranean Region (IMEMR), one of the major projects of the Virtual Health Sciences Library (VHSL), was initiated in response to a pressing need to index health and biomedical journals. Currently, the Index includes more than 180 000 bibliographic citations from more than 645 health and biomedical journals published in 20 countries of the Region: Afghanistan, Bahrain, Egypt, Iraq, Islamic Republic of Iran, Jordan, Kuwait, Lebanon, Libya, Morocco, Oman, Pakistan, occupied Palestinian territory, Qatar, Saudi Arabia, Sudan, Syrian Arab Republic, Tunisia, United Arab Emirates and Yemen.
National Library of Pakistan
It serves as the national repository for Books, Research Papers, Legal Deposits, Reports, Newspapers & Periodicals. And also, the official depository of International organizations including Asian Development Bank, International Labor Organization and UNESCO, etc. It preserves all the deposited published literature provides open access to the researchers.