the study was conducted in 10 laboratories where the minimum inhibitory concentrations of six antibiotics ( carbenicillin , cefoxitin , chloramphenicol , clindamycin , penicillin g , and tetracycline ) were determined against 10 bacterial strains on wilkins-chalgren agar prepared by three manufacturers .
C0006976
carbenicillin
C0030827
penicillin g