An Asymptotic Reduction of a Painleve' VI equation to a Painleve' III (January 2011).

link: http://arxiv.org/abs/1101.4705
Abstract

When the independent variable is close to a critical point, it is shown that
PVI can be asymptotically reduced to PIII. In this way, it is possible to
compute the leading term of the critical behaviors of PVI transcendents
starting from the behaviors of PIII transcendents.