Pasquale Ciarletta Paolo Dario Frank Tendick Silvestro Micera Hyperelastic Model of Anisotropic Fiber Reinforcements within Intestinal Walls for Applications in Medical Robotics. 1279-1288 2009 28 I. J. Robotic Res. 10 http://dx.doi.org/10.1177/0278364909101190 db/journals/ijrr/ijrr28.html#CiarlettaDTM09