@article{10_4153_CMB_2011_184_7,
     author = {Filali, M. and Monfared, M. Sangani},
     title = {A {Cohomological} {Property} of \ensuremath{\pi}-invariant {Elements}},
     journal = {Canadian mathematical bulletin},
     pages = {534--543},
     year = {2013},
     volume = {56},
     number = {3},
     doi = {10.4153/CMB-2011-184-7},
     url = {http://geodesic.mathdoc.fr/articles/10.4153/CMB-2011-184-7/}
}