Science Citation Index Expanded (Web of Science) (1955+) Provides access to current bibliographic information and cited references. Covers approximately 5,800 of the world's leading scientific and technical journals in a broad range of disciplines.
American Institute of Physics Full-text to selected journals produced by the American Institute of Physics, including the American Astronomical Society.
arXiv.org e-Print archive (Los Alamos National Laboratory e-Print Archive) (1991+) Provides access to an automated archives for electronic communication of research information in many fields of physics, and some related and unrelated disciplines.
Astrophysics Data System Abstract Service (ADS Abstract Service) (1995+) NASA-funded service provides access to four sets of abstracts: 1) astronomy and astrophysics/planetary sciences/solar physics; 2) instrumentation; 3) physics and geophysics; and 4) Los Alamos preprint server.