@article{701668,
     title = {Irreducible holonomy representations},
     booktitle = {Proceedings of the 20th Winter School "Geometry and Physics"},
     series = {GDML\_Books},
     publisher = {Circolo Matematico di Palermo},
     address = {Palermo},
     year = {2001},
     pages = {59-81},
     mrnumber = {MR1831947},
     zbl = {1037.53034},
     url = {http://dml.mathdoc.fr/item/701668}
}

Schwachhöfer, Lorenz J. Irreducible holonomy representations, dans Proceedings of the 20th Winter School "Geometry and Physics", GDML_Books,  (2001), pp. 59-81. http://gdmltest.u-ga.fr/item/701668/