General Act of the Berlin Conference on West Africa, 26 February 1885
… of the Ottomans, WISHING, in a spirit of good and mutual accord, to regulate the conditions most favourable to the … years, whether it may be necessary to revise, by common accord, the abovementioned tariffs. Article 15 The affluents … to introduce into it subsequently, and by common accord, such modifications and improvements as experience may …