Gloriam DE, Schiöth HB, Fredriksson R (2005). "Nine new human Rhodopsin family G-protein coupled receptors: identification, sequence characterisation and evolutionary relationship". Biochim. Biophys. Acta. 1722 (3): 235–46. doi:10.1016/j.bbagen.2004.12.001. PMID15777626.