A DOI (digital object identifier) is a unique alphanumeric string assigned to a digital object such as an electronic journal article, a conference paper or a book chapter. A DOI uniquely identifies the content item and provides a persistent link to its location on the internet. Look for the DOI as part of reference lists or citations. If you know the DOI of a paper (looks like this: doi:10.1007/s10067-006-0283-5), you can find the paper using a DOI Resolver.
Science 4 October 2013:
Vol. 342 no. 6154 pp. 60-65
INSPEC and Compendex on Engineering Village
For all major engineering, computer science, physics and applied science topics these two databases represent the major access points to the literature. This is the place to start any literature search!
National Library of Medicine's database of biomedical journal literature providing access to information on the following: population and reproductive biology, medicine, nursing, dentistry, veterinary medicine, the health care system, the preclinical sciences, and allied health. Coverage is worldwide with an emphasis on English-language peer reviewed journals.
Indexes international economic literature. Includes major journals, articles in collective volumes (essays, proceedings, etc.), books, full-text book reviews, dissertations, and working papers.
Produced by the American Psychological Association, it is the most comprehensive database of psychology. Provides abstracts and citations to the scholarly literature in the behavioral sciences and mental health.