Here is Oliver O’Donovan’s review of Paul Avis’ Beyond Reformation? posted on T & T Clark’s blog:

Paul Avis’s study is a timely reminder of the importance of the late–medieval conciliar tradition for questions about the reformation and reunification of the Western church. A historian and a practical ecumenist, he shows us the pervasive influence of conciliarist constitutional principles through the intervening centuries, as well as their continuing relevance to our contemporary search for Christian unity. There is much to be learned here by those who concern themselves with the church in our times and its roots in the past.