da Silva R. M. P., Caridade S. G., SanRamon J., Mano J. F., and Reis R. L.,  "Transport of small anionic and neutral solutes through chitosan membranes: Dependence on cross-linking and chelation of divalent cations",  Biomacromolecules , vol. 9, issue 8, pp. 2132-2138, 2008.