1. Hagen, G. P., Schmidt, G. E., Weis, J. M., Smith, T. G, U. S. Pat., 5138098(1992).
2. “Preparation and application of 2,6-naphthalene dicarboxylic acid and dimethyl-2, 6-naphthalene dicarboxylate”;He;Coal Chem. Ind.,2001
3. Friedel-Crafts and Related Reactions;Olah,1964
4. Hagen, G. P., Schmidt, G., E., Weis, J. M., Smith. T. G., U. S. Pat., 5026917(1991).
5. “Solubility of trioxane in water”;Brandani;J. Chem. Eng. Data.,1994