2307/1562791. The sixth sense in mammalian forerunners: Variability of the parietal foramen and the evolution of the pineal eye in South African Permo-Triassic
Ramon F. Rod Vision: Pathways and Processing in the Mammalian Retina. Progress in Retinal and Eye Research. 2001, 20 (3): 351–384. doi:10.1016/S1350-9462(00)00031-8