Rego, Angela, Francisco Sousa, Telma Feliciano, and Cecília Almeida e Sousa. “Positional Downbeat Nystagmus: A Narrative Review”. Portuguese Journal of Otorhinolaryngology and Head and Neck Surgery 59, no. 3 (September 4, 2021): 273–278. Accessed October 27, 2024. https://journalsporl.com/index.php/sporl/article/view/2890.