https://api.elsevier.com/content/article/pii/S0960077921000710doi:10.1016/j.chaos.2021.1107181-s2.0-S096007792100071010.1016/j.chaos.2021.110718S0960-0779(21)00071-0The Cyclicity of coronavirus cases: “Waves” and the “weekend effect” Chaos, Solitons & FractalsJournal096007792021-03-31March 20210falsefalse