acute exacerbations of chronic bronchitis
... that acute exacerbations of chronic bronchitis occur on average two to three times per year in a person suffering from chronic obstructive pulmonary disease?
... that <b id="mwCAU"><a class="mw-redirect" href="./Acute_exacerbations_of_chronic_bronchitis" id="mwCAY" rel="mw:WikiLink" title="Acute exacerbations of chronic bronchitis">acute exacerbations of chronic bronchitis</a></b> occur on average two to three times per year in a person suffering from <a href="./Chronic_obstructive_pulmonary_disease" id="mwCAc" rel="mw:WikiLink" title="Chronic obstructive pulmonary disease">chronic obstructive pulmonary disease</a>?