@article{SLC_1998_41_a2, author = {Helmut Kr\"amer}, title = {Eigenspace {Decompositions} with {Respect} to {Symmetrized} {Incidence} {Mappings}}, journal = {S\'eminaire lotharingien de combinatoire}, year = {1998}, volume = {41}, url = {http://geodesic.mathdoc.fr/item/SLC_1998_41_a2/} }