@article{article,
title = {Value of serum and bronchoalveolar lavage fluid immunoglobulin G subclass levels and serum immunoglobulins in the management of chronic obstructive pulmonary disease},
author = {},
year = {1997},
journal = {European Respiratory Journal Suppl.},
volume = {10},
number = {25},
pages = {208S, Sept},
howpublished = "\url{https://eurekamag.com/research/034/179/034179315.php}"
}