Bilbao Crystallographic server: www.cryst.ehu.es

Webelements: www.webelements.com

Resources for Electronic Structure: electronicstructure.org

Quantum Espresso Package: www.quantum-espresso.org

Plane Wave Pseudopotential code: www.pwscf.org

Center for Computational Materials Science: www-cst.nrl.navy.mil

Quasiamore group at MIT: quasiamore.mit.edu

ErMeS at NCSU: ermes.physics.ncsu.edu

Electronic Structure DB at NIST: physics.nist.gov

Landolt-Bornstein searchable DB: lb.chemie.uni-hamburg.de