- Tours to Bulgaria >>> Cooperation Cooperation c Travel Agents PALLADA-AVIATURLearn how to offer and conditions of cooperation with the Travel Agents PALLADA-AVIATUR.. Agreement on Provision of travel services | | | | | | The Treaty on tourist travel booking | | | Our documents  |  |  | Air services sale Certificate of State Aviation Administration of Ukrainе | State registration Certificate | License of State Tourism Administration of Ukraine | |