Comparative effectiveness of third doses of mRNA-based COVID-19 vaccines in US veterans. - Dickerman BA; Gerlovin H; Madenci AL; Figueroa Muñiz MJ; Wise JK; Adhikari N; Ferolito BR; Kurgansky KE; Gagnon DR; Cho K; Casas JP; Hernán MA (Nature microbiology, 2023)