Nélisse, H., C. Laroche, J. Boutin, C. Giguere, and V. Vaillancourt. “Propagation of Sound Behind Vehicles Equipped With Different Backup Alarms”. Canadian Acoustics, vol. 39, no. 3, Sept. 2011, pp. 114-5, https://jcaa.caa-aca.ca/index.php/jcaa/article/view/2437.