Towards a digital model to edit the different paratextuality levels within a textual tradition

In the textual tradition of a literary work, our sources (manuscripts, printed books etc.) commonly bear, together with the "main text", different kinds of "paratexts" commenting on it (including interlinear annotations, glosses, scholia, footnotes, modern scholarly introductions and commentaries, and many others). This article proposes a unified model for a document-based digital critical edition including both the  main texts  and the  paratexts  as they appear in different single sources. The problematic aspects of such an "enlarged" digital edition are discussed, including the relations between the different  paratexts  and the  main text  they refer to  within each single textual source , as well as the "alignment" of different  main texts  and  paratexts  in different sources.