ANERAO, A.; PATIL, B.; PRADHAN, N. DETERMINATION OF RESIDUAL DIMETHYL SULFATE IN METHOXSALEN DRUG SUBSTANCE BY PRE-COLUMN DERIVATIZATION WITH STATIC HEADSPACE GAS CHROMATOGRAPHY. International Journal of Pharmacy and Pharmaceutical Sciences, v. 10, n. 8, p. 84-89, 1 Aug. 2018.