Götz Pfeiffer and Gerhard Röhrle,
Special Involutions and Bulky Parabolic Subgroups in Finite Coxeter Groups.
J. Aust. Math. Soc., 79 (2005), 141-147.
arXiv:math.GR/0406014.
Abstract.
The conjugacy classes of so-called special involutions parameterize
the constituents of the action of a finite Coxeter group on the
cohomology of the complement of its complexified hyperplane
arrangement. In this note we give a short intrinsic characterisation
of special involutions in terms of so-called bulky parabolic
subgroups.
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