- Cross-resistance, relatedness and allele analysis of fluoroquinolone-resistant US clinical isolates of Streptococcus pneumoniae (1998-2000). Davies, T.A., Goldschmidt, R., Pfleger, S., Loeloff, M., Bush, K., Sahm, D.F., Evangelista, A. J. Antimicrob. Chemother. (2003)