R. Cogo, A. Ramponi, and G. Scivoletto, et al., “Prophylaxis for acute exacerbations of chronic bronchitis using an antibacterial sublingual vaccine obtained through mechanical lysis: a clinical and pharmacoeconomic study”, Acta Biomed, vol. 74, no. 2, pp. 81–87, Aug. 2003, Accessed: Apr. 24, 2026. [Online]. Available: https://mattioli1885journals.com/index.php/actabiomedica/article/view/2129