1VND:
reference: The three-dimensional solution structure of the NK-2 homeodomain from Drosophila., Tsao DH, Gruschus JM, Wang LH, Nirenberg M, Ferretti JA, J Mol Biol 1995 Aug 11;251(2):297-307. PMID: 7643404

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