The original article reported by Dr. Kubota was published in Diagn Microbiol Infect Dis.
K. Kubota , Y. Kitagawa , M. Matsuoka , K. Imai , Y. Orihara , R. Kawamur, J. Sakai , N. Ishibashi , N. Tarumoto , S. Takeuchi , S. Maesaki , T. Maeda.
Clinical evaluation of the antibody response in patients with COVID-19 using automated high-throughput immunoassays. 【Pubmed】