HIV Capsid image source: http://pdb101.rcsb.org/motm/163
Edit/Update:
HIV Hexamer image source: https://www.scripps.edu/news-and-events/press-room/2009/061209.html
HIV-1 Capsid Pentamer-Hexamer image source: https://on-demand.gputechconf.com/gtc/2013/webinar/gtc-express-hiv-capsid.pdf
HIV Architecture image source: https://www.cgl.ucsf.edu/chimera/data/hiv-drug-nov2011/hiv-demo.html
"X-ray structures of the hexameric building block of the HIV capsid." - https://www.ncbi.nlm.nih.gov/pubmed/19523676