@article{701742,
     title = {$Q$-curvature and spectral invariants},
     booktitle = {Proceedings of the 24th Winter School "Geometry and Physics"},
     series = {GDML\_Books},
     publisher = {Circolo Matematico di Palermo},
     address = {Palermo},
     year = {2005},
     pages = {[11]-55},
     mrnumber = {MR2152355},
     zbl = {1101.53016},
     url = {http://dml.mathdoc.fr/item/701742}
}

Branson, Thomas. $Q$-curvature and spectral invariants, dans Proceedings of the 24th Winter School "Geometry and Physics", GDML_Books,  (2005), pp. [11]-55. http://gdmltest.u-ga.fr/item/701742/