2W4G:
reference: Methods for identifying and averaging variable molecular conformations in tomograms of actively contracting insect flight muscle., Wu S, Liu J, Reedy MC, Winkler H, Reedy MK, Taylor KA, J Struct Biol. 2009 Dec;168(3):485-502. Epub 2009 Aug 19. PMID: 19698791

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