Mathkar, S.; Kumar, S.; Bystol, A.; Olawoore, K.; Min, D.; Markovich, R.; Rustum, A.: The use of differential scanning calorimetry for the purity verification of pharmaceutical reference standards, in: J. Pharm. Biomed. Anal., 2009, 49, S. 627–631; doi:10.1016/j.jpba.2008.12.030.