Arnold, K., Davies, B., Giles, R., Grosjean, C., Smith, G., & Whiting, A. (2006). To catalyze or not to catalyze? Insight into direct amide bond formation from amines and carboxylic acids under thermal and catalyzed conditions. Advanced Synthesis & Catalysis, 348(7-8), 813-820. https://doi.org/10.1002/adsc.200606018