The Universal Postal Union (UPU) - Bibliography
Annual Report of the Work of the Union . Résumé and general review of UPU activities.
Collection of Postal Studies . A series of publications concerning topics studied by the UPU.
Union Postale . Quarterly. Parallel text in the seven languages of the union—Arabic, Chinese, English, French, German, Russian, and Spanish. Contains articles on postal services and information on UPU activities.
The Universal Postal Union . (brochure) A brief outline of UPU features.