Optical vortices in waveguides with discrete and continuous rotational symmetryAndrey Pryamikov, Ljupco Hadzievski, Mikhail Fedoruk, Sergei Turitsyn and Alejandro AcevesJ. Eur. Opt. Soc.-Rapid Publ., 17 1 (2021) 23DOI: https://doi.org/10.1186/s41476-021-00168-5
