Institutions:

• SAO/NASA ADS Astronomy Query Form
• Cornell University Astrophysics Authors
• SIMBAD Astronomical Database
• NASA/IPAC Extragalactic Database – NED
• XMM-Newton Science Operations Centre
• Chandra X-Ray Observatory (CXC)
• Fermi Science Support Center (FSSC)

Related links regarding Exoplanets:

• exoplanet.eu
• www.hzgallery.org
• kepler.nasa.gov