I am looking for a list of global cities. By global city I mean "Global cities are major “corporate and financial hubs” in a “global web of linkages”, based on the functional perspective in urban studies" (Wang, 2019). In the literature it seems that different researchers are using different global cities in their analysis. From what I have read so far, it seems that there no universal convergence regarding the definition of a global city.
To clarify, by global city I don't mean a city with population greater than 10 million (i.e., megacity). So, is there any research or book (relatively recent) that lists the global megacities?