Electron microscopy of SARS-CoV-2: a challenging task – Authors' reply. Issue 10238 (30th May 2020) - Varga, Zsuzsanna; Flammer, Andreas J; Steiger, Peter; Haberecker, Martina; Andermatt, Rea; Zinkernagel, Annelies; Mehra, Mandeep R; Scholkmann, Felix; Schüpbach, Reto; Ruschitzka, Frank; Moch, Holger