El Mouridi, M., T. Laurent, L. Brancheriau, O. Arnould, A. Famiri, A. Hakam, and J. Gril. “Searching for Material Symmetries in the Burr Wood of Thuja by a Direct Contact Ultrasonic Method on Spherical Samples”. Maderas-Cienc Tecnol, vol. 13, no. 3, Dec. 2014, pp. 285-96, https://revistas.ubiobio.cl/index.php/MCT/article/view/1308.