Experimental Study into Optimal Configuration and Operation of Two-Four Rotor Coaxial Systems for eVTOL Vehicles.Published in:Aerospace (MDPI Publishing), 2022, v. 9, n. 8, p. N.PAG, doi. 10.3390/aerospace9080452By:Prasad Rao, Jubilee;Holzsager, Jonathan E.;Maia, Marco M.;Diez, Javier F.Publication type:Article