Technical reports

Many organisations make their research reports available for general use. Some of the major sources include

Information Bridge
Provides the open source to full-text and bibliographic records of the [U.S.] Department of Energy (DOE) research and development reports across many fields. Full coverage starts in 1995

NTIS: National Technical Information Service
A searchable database of technical reports from U.S. government sponsored research issued since 1990

NTRS: NASA Technical reports Server
Over 840,000 collects scientific and technical information