Rook, L., Bondioli, L., Köhler, M., Moyà-Solà, S., & Macchiarelli, R. (1999). Oreopithecus was a bipedal ape after all: Evidence from the iliac cancellous architecture. The National Academy of Sciences.

Rook, Lorenzo, Luca Bondioli, Meike Köhler, Salvador Moyà-Solà, and Roberto Macchiarelli. Oreopithecus Was a Bipedal Ape After All: Evidence From the Iliac Cancellous Architecture. The National Academy of Sciences, 1999.

Rook, Lorenzo, et al. Oreopithecus Was a Bipedal Ape After All: Evidence From the Iliac Cancellous Architecture. The National Academy of Sciences, 1999.