1. For reviews on this subject, see:
2. The synthesis of natural β-lactam antibiotics
3. , , , E. Hunt in Recent Progress in the Chemical Synthesis of Antibiotics and Related Microbial Products (Ed.: , Springer, Berlin, 1993 , , p. 621.
4. I. Ojima in The Organic Chemistry of β-Lactams (Ed.: , VCH, New York, 1993 , p. 197.
5. The Chemistry of β-Lactams (Ed.: , Chapman and Hall, London, 1992 .