4RMP:
reference: Crystal Structure of Allophycocyanin from Marine Cyanobacterium Phormidium sp. A09DM., Sonani RR, Gupta GD, Madamwar D, Kumar V, PLoS One. 2015 Apr 29;10(4):e0124580. doi: 10.1371/journal.pone.0124580., eCollection 2015. PMID: 25923120

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