title: Penicillin-resistant pneumococci in the United States.
authors.forename: E O
authors.initials: EO
authors.lastname: Mason
authors.forename: S L
authors.initials: SL
authors.lastname: Kaplan
mesh_terms: D006801:Humans; D008826:Microbial Sensitivity Tests; D010403:Penicillin Resistance; D011008:Pneumococcal Infections / Q000188:drug therapy* / Q000453:epidemiology; D013296:Streptococcus pneumoniae / Q000187:drug effects*; D014481:United States / Q000453:epidemiology