Kiese-Himmel, Christiane, Wolfgang Himmel, and Martin Scherer. “Is a Change in Vocal Loudness a First Step towards Becoming a Medical Doctor?”. Swiss Medical Weekly 142, no. 0910 (February 26, 2012): w13534. Accessed November 24, 2024. https://smw.ch/index.php/smw/article/view/1438.