%0 Journal Article %J Nature %D 2012 %T Three-dimensional limb joint mobility in the early tetrapod Ichthyostega %A S.E. Pierce %A J.A. Clack %A J.R, Hutchinson %B Nature %V 486 %P 523-526 %G eng %U http://www.nature.com/nature/journal/v486/n7404/full/nature11124.html