The authors original matlab and C code associated with their paper:

Kobayashi R, Tsubo Y, and Shinomoto S.
Made-to-order spiking neuron model equipped with a multi-timescale
adaptive threshold.
Frontiers in Computational Neuroscience 3:9 (2009)

is available from the authors web site:

The matlab code when run without parameter changes reproduces the RS
spike trace in Fig 5b: