- Schrijver, Peter. 2011b. 'Middle and Early Modern Breton', Elmar Ternes (éd.), Brythonic Celtic – Britannisches Keltisch, Bremen: Hempen, 359–429.
Parina (2012), review: "He starts with a short chronology of the period described and a list of Middle Breton sources. The next section, Middle Breton metrics (pp.365–367), is very useful. It is regrettable that we have no such discussions of Middle Welsh and Middle Cornish data in this book. Then follows the description of phonology and spelling presented in a reader-friendly way. The discussion of initial mutations is rather short (pp.387–388), with no indications of triggers of mutations. The author simply gives a reference to the corresponding section in the Modern Breton chapter (p.388). But since we know that in Middle Welsh the rules of mutations were not identical with those in Modern Welsh (see e.g. Sims-Williams 2010), there is no way of ruling out a similar diﬀerence between Middle and Modern Breton, so that a list of attested mutation triggers for this very period would have been desirable. Within the section on morphology there is an important piece on the semantics of tenses (pp.402–403). Similar discussions, unfortunately, are lacking in other chapters. As regards the section on syntax, we tried to ascertain when the quet element entered the negative sentence, but though three examples of nine representing diﬀerent types of negative sentences have quet, the author does not pay it any attention (p.416). The chapter closes with a very short note on the origins of the vocabulary (pp.418–419), a short piece on Early Modern Breton (pp.419–420), a selection of three texts, all poetic, and a bibliography."
- Sims-Williams, Patrick. 2010. 'The spread of sandhi h-' in thirteenth-century Welsh', TPS 108, 41-52.