Crystallography Open Database (COD): an open-access collection of crystal structures and platform for world-wide collaboration. - Saulius Grazulis; Adriana Daskevic; Andrius Merkys; Daniel Chateigner; Luca Lutterotti; Miguel Quirós; Nadezhda R. Serebryanaya; Peter Moeck; Robert T. Downs; Armel Le Bail (Nucleic Acids Res., 2012)