). T. Verbiest, K. Clays, C. Samyn, J. Wolff, D. Reinhoudt et al., Investigations of the Hyperpolarizability in Organic Molecules from Dipolar to Octopolar Systems, Journal of the American Chemical Society, vol.116, issue.20, p.9320, 1994.
DOI : 10.1021/ja00099a058