Evaluating matrix functions by resummations on graphs: The method of path-sums

by Giscard, P.-L., Thwaite, S.J., Jaksch, D.
Published 2014

An exact formulation of the time-ordered exponential using path-sums

by Giscard P.-L., Lui K., Thwaite S.J., Jaksch Dieter Hans
Published 2016