Analysis of The Influence of Pre-Flight Service Quality, In-flight Service Quality, Post-Flight Service Quality, and Covid-19 Protocol Service Quality Towards Passenger Satisfaction and Passenger Loyalty of Lion Air Passenger in Medan Journal title: Journal of Economics, Finance and Management Studies Authors: Michelle Elvina,Ronald Suryaputra,Amelia Subject(s): Economics, Banks and Banking, Marketing, Accounting, Management, Business, Finance