4NX4:
reference: Protein structural ensembles are revealed by redefining X-ray electron density noise., Lang PT, Holton JM, Fraser JS, Alber T, Proc Natl Acad Sci U S A. 2014 Jan 7;111(1):237-42. doi: 10.1073/pnas.1302823110., Epub 2013 Dec 20. PMID: 24363322

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