# The cluster set from Figure 1 of van Iersel, Kelk, Rupp & Huson (2010).
# The galled-network algorithm needs four reticulations for this input;
# Cass finds the level-2 network with two reticulations.
a b f g i
a b c f g i
a b f i
b c f i
c d e h
d e h
b c f h i
b c d f h i
b c i
a g
b i
c i
d h
