Antibiotic resistance among clinical isolates of Hemophilus influenzae in the United States in 1994 and 1995 and detection of β-lactamase-positive strains resistant to amoxicillin-clavulanate: Results of a national multicenter surveillance study - Doern,G.V.; Brueggemann,A.; Pierce,G.; Holley Jr,P.H.; Rauch,A. (Antimicrob Agents Chemother, 1997)