Hazards in the publications calendar of the Honoré Champion editions mean that this book, clearly completed in 2013, did not come into being until 2015, and thus after the volume led by Karin Üeltschi, L’Univers du livre medieval (Substance, letter, sign), which appeared in the same collection in 2014 and which could a priori be regarded as exploring a neighbouring territory. Indeed, an editorial note would have been welcome, especially as Gérard Gros’ preface, dated September 2013, occupies t...