Mortality in severe serious adverse events following heterologous and homologous prime-boost vaccination strategies for SARS-CoV-2: A retrospective cohort study - Min Cheol Song; Jongmok Ha; Suyeon Park; Hyunwook Kang; Taeeun Kyung; Namoh Kim; Dong Kyu Kim; Kihoon Bae; Kwang Jun Lee; Euiho Lee; Jin Myoung Seok; Jinyoung Youn (PLoS ONE, 2025)