M. Riccò, “RT-qPCR assays based on saliva rather than on nasopharyngeal swabs are possible but should be interpreted with caution: results from a systematic review and meta-analysis.: Diagnosis of SARS-CoV-2 through salivary fluids”, Acta Biomed, vol. 91, no. 3, p. e2020025, Sep. 2020, doi: 10.23750/abm.v91i3.10020.