Following the rise of the universities around 1200, the growth in secular production and in consumer demand led to increasing specialization and commercialization in book production. A group of middlemen, known as stationers (cartolai in Italy, libraires in France), emerged. They supplied materials to craftsmen and received and subcontracted commissions, often with formal recognition from the universities. This decentralization stimulated new techniques of book production, such as the systematic marking up of leaves and quires for assembly by the stationer and the provision of instructions. See also pecia system.
Michelle Brown, Understanding Illuminated Manuscripts (Malibu, CA: J. Paul Getty Museum in association with the British Library, c1994).