9th International BAPT Conference "Power Transmissions 2023" : Varna, Bulgaria, September 4-7, 2023
8th International BAPT Conference "Power Transmissions 2022" : Varna, Bulgaria, September 5-8, 2022
19th International Stirling Engine Conference (ISEC 2021) : Rome, Italy, September 22-23, 2021
7th International BAPT Conference "Power Transmissions 2020" : Borovets, Bulgaria, June 10-13, 2020