Manneganti, Vijay, et al. “SO3H-Carbon Derived from Glycerol: An Efficient and Recyclable Catalyst for Smooth and Regioselective Azidolysis of Oxiranes in Water”. European Journal of Chemistry, vol. 5, no. 1, Mar. 2014, pp. 167-70, doi:10.5155/eurjchem.5.1.167-170.917.