1. Broadhurst, M.J., Grigg. R. and Johnson, A.W.: J. Chem. Soc., Perkin Trans. 1 (1972) 2111.
2. Dolphin, D. (ed.): “The Porphyrins”, New York: Academic, 1978.
3. IUPAC-IUB Joint Commission on Biochemical Nomenclature: Pure and Appl. Chem. 51 (1979) 2251; Eur. J. Biochem. 108 (1980) 1.
4. Milgrom, L.R.: “The Colours of Life“, Oxford: OUP, 1997.
5. (a) Sessler, J.L. and Weghorn S.J.: “Expanded, contracted and isomeric porphyrins”, Oxford: Elsevier 1997 and references therein: (b) Sessler, J.L., Gebauer, A. and Weghorn, S.J.: “Expanded porphyrins.”, in: “The porphyrin Handbook”, Kadish, K.M., Smith, K.M. and Guilard, R. (eds.), New York: Academic Press, 2000.