SARS-CoV-2 variant evolution in the United States: high accumulation of viral mutations over time likely through serial Founder Events and mutational bursts - Tasakis, Rafail Nikolaos; Samaras, Georgios; Jamison, Anna; Lee, Michelle; Paulus, Alexandra; Whitehouse, Gabrielle; Verkoczy, Laurent; Papavasiliou, Nina; Diaz, Marilyn (PLOS ONE, 2021)