FCAP, Stewart Comer MD. “Longitudinal Performance Validation of Siemens SARS-CoV-2 Spike Protein Serologic Assay”. Archives of Clinical and Medical Case Reports 5, no. 6 (November 8, 2021): 807–810. Accessed June 15, 2026. https://fortunejournals.org/ojs/index.php/acmcr/article/view/22554.