§1. To be published, catechisms and other writings pertaining to catechetical instruction or their translations require the approval of the local ordinary, without prejudice to the prescript of can. 775, §2.
§2. Books which regard questions pertaining to sacred scripture, theology, canon law, ecclesiastical history, and religious or moral disciplines cannot be used as texts on which instruction is based in elementary, middle, or higher schools unless they have been published with the approval of competent ecclesiastical authority or have been approved by it subsequently.
§3. It is recommended that books dealing with the matters mentioned in §2, although not used as texts in instruction, as well as writings which especially concern religion or good morals are submitted to the judgment of the local ordinary.
§4. Books or other writings dealing with questions of religion or morals cannot be exhibited, sold, or distributed in churches or oratories unless they have been published with the permission of competent ecclesiastical authority or approved by it subsequently.
Source: Code of Canon Law (Vatican.va)