@article{JLT_2007_17_2_JLT_2007_17_2_a0,
     author = {J.-G. Luque and J.-C. Novelli and J.-Y. Thibon},
     title = {Period {Polynomials} and {Ihara} {Brackets}},
     journal = {Journal of Lie theory},
     pages = {229--239},
     year = {2007},
     volume = {17},
     number = {2},
     url = {http://geodesic.mathdoc.fr/item/JLT_2007_17_2_JLT_2007_17_2_a0/}
}