The manuscripts
The only surviving manuscript (Avranches, Bibliothèque municipale, MS 162) is derived from the monastery of Mont St Michel; another (now lost), from which the editio princeps of 1582 was derived, is known to have been in Bec. The Mont St. Michel manuscript that dates from the second half of the twelfth century was probably a copy of that from the abbey of Bec. Robert of Torigni (died 1186), the Norman historian who was a monk of Bec and then became Abbot of Mont St Michel in 1154 was almost certainly responsible for this.
Modern editions
Muratori, L.A., Guilielmi Appuli Historicum poema de rebus Normannorum in Sicilia, Appulia et Calabria gestis..., in Rerum Italicarum Scriptores, vol. v, Rome, 1724, reprinted in Migne, J.P., Patrologie latina, vol. 149, Paris, Garnier, 1882, columns 1027-1082.
R. Wilmans Guillermi Apuliensis Gesta Roberti Wiscardi, in Monumenta Germania Historica, Scriptores, vol. ix, 1851, reprinted 1925.
Mathieu, M., (ed.), Guillaume de Pouille: La Geste de Robert Guiscard, Palermo, Istituto siciliano di studi bizantini e neoellenici, Testi 4, 1961.
Critical studies
Pagano, A., Il poema Gesta Roberti Wiscardi di Guglielmo Pugliese, Naples, 1909 is a useful, if dated critical study of the poem.
M. Mathieu introduction to her edition of Guillaume de Pouille, Palermo, 1961, pp. 3-96
Wolf, K.B., Making History: The Normans and their Historians in Eleventh-Century Italy, Philadelphia 1995, pp. 123-142.
Albu, E., The Normans and their Histories: Propaganda, Myth and Subversion, Woodbridge 2001, pp. 106-144.
Loud, G.A., ‘Anna Komnena and her sources for the Normans of southern Italy’, in Wood, I.N. & Loud ,G.A., (eds.), Church and Chronicle in the Middle Ages. Essays Presented to John Taylor, (Hambledon), 1991, pp. 41-57, reprinted in Loud, G.A., Conquerors and Churchmen in Norman Italy, (Ashgate), 1999.