Bilbao Crystallographic server: www.cryst.ehu.es

Webelements: www.webelements.com

Isotropy Software Suite: iso.byu.edu/iso/isotropy

AFLOW an AFLOWlib: aflow.org

Resources for Electronic Structure: electronicstructure.org

Quantum Espresso Package: www.quantum-espresso.org

Electronic Structure DB at NIST: physics.nist.gov

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

Pseudos: sites.google.com/site/dceresoli/pseudopotentials, Theos