4HCK:
reference: Solution structure of the human Hck SH3 domain and identification of its ligand binding site., Horita DA, Baldisseri DM, Zhang W, Altieri AS, Smithgall TE, Gmeiner WH, Byrd RA, J Mol Biol 1998 Apr 24;278(1):253-65. PMID: 9571048

This OCA Structure page
uses Jmol, developed by the Jmol Development Team (documentation).