B. Akinci Ozyurek, S. Sarinc Ulasli, S. Savas Bozbas, N. Bayraktar, and S. Akcay, “Value of serum and induced sputum surfactant protein-D in chronic obstructive pulmonary disease”, Multidiscip Respir Med, vol. 8, no. 9, Jun. 2013, doi: 10.4081/mrm.2013.534.