IDENTIFICATION AND QUANTITATIVE DETERMINATION OF ACTIVE PHARMACEUTICAL INGREDIENTS IN SUPPOSITORIES BY A COMBINATION OF 1H NMR SPECTROSCOPY AND DESORPTION MASS SPECTROMETRY Article Kalabin G.A., Goryainov S.V., Ivlev V.A., Niftullaev F.Yu., Abramovich R.A. Russian Chemical Bulletin. Vol. 63. 2014. P. 1848-1855