Prospective comparison of transbronchial needle aspiration biopsy (TBNA) and endosonography-guided biopsy (EUS-FNA) of mediastinal lymph nodes in patients with know or suspected non-small cell lung cancer [abstract] - Wiersema,M.J.; Edell,E.S.; Midthun,D.E. (Gastroinest Endosc, 2002)