S.  Chandra, Kundu, T., Kandambeth, S., BabaRao, R., Marathe, Y. N., Kunjir, S. M., and Banerjee, R., ?Phosphoric acid loaded azo (-N=N-) based covalent organic framework for proton conduction?, Journal of the American Chemical Society, vol. 136, no. 18, pp. 6570-6573, 2014.