1. C-3′Quaternary Ammonium Cephems, a New Wave of Cephalosporins
André Bryskier 
Clinical Microbiology and Infection 
Volume 1, Issue 1, Pages 1-3 (September 1995)
DOI: /j tb00015.x
Copyright © 1995 European Society of Clinical Infectious Diseases Terms and Conditions

2. Figure 1 C-3′ quaternary ammonium cephems.
Clinical Microbiology and Infection 1995 1, 1-3DOI: ( /j tb00015.x)
Copyright © 1995 European Society of Clinical Infectious Diseases Terms and Conditions

3. Figure 2 Quaternary ammonium cephems.
Clinical Microbiology and Infection 1995 1, 1-3DOI: ( /j tb00015.x)
Copyright © 1995 European Society of Clinical Infectious Diseases Terms and Conditions