RT Journal Article SR Electronic T1 Muscarinic receptor subtypes in airways JF European Respiratory Journal JO Eur Respir J FD European Respiratory Society SP 328 OP 331 DO 10.1183/09031936.93.06030328 VO 6 IS 3 A1 PJ Barnes YR 1993 UL http://erj.ersjournals.com/content/6/3/328.abstract AB