The second chapter is devoted to the transitional period of the fifteenth and sixteenth centuries, during which printed books came to replace manuscripts. Books discussed in this chapter had an important manuscript tradition in earlier centuries. In continental Europe, legal incunabula and early-sixteenth-century imprints included mainly the fundamental compilations of civil (Azo, Accursius, Bartolus, Baldus, Tartagni) and canon (Gratian, Hostiensis, Durantis, Panormitanus) law, setting out the curriculum of law studies, in which the text of the compilation was often surrounded by a comprehensive system of glosses, commentaries, summae, and collections of learned opinions produced for political authorities or private litigants in specific cases. But there were also some important works on customary law (e.g. the Saxon Mirror in German territories, Bracton and Littleton in England, Boutillier in France).