Brandão, Lui­s Eduardo Barreira, et al. “A New Method for Estimation of the Transient Time Using Fourier Transform Associated With Cross-Correlation Techniques to Measure Flow Rate in Pipelines Using Radiotracers”. Instituto De Engenharia Nuclear: Progress Report, nº 4, agosto de 2021, https://revistas.ien.gov.br/index.php/ienprogressreport/article/view/495.