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Hughes D, Corrado MM, Mynatt I, Prats M, Royall NA, Boulger C, Bahner DP.Hughes D, et al. Among authors: royall na.Ultrasound J. 2020 Feb 28;12(1):8. doi: 10.1186/s13089-020-0157-0.Ultrasound J. 2020.PMID: 32108277Free PMC article.