1. Thin Layer Chromatography;Santavy,1969
2. T. L. C. Identification of opium alkaloids by Denige's reagent;Guven;Eczacilik Bull.,1973
3. Thin layer chromatographic identification of opium and its alkaloids;Rama Rao;J. Indian Acad. Forensic Sci.,1974
4. False positive alkaloid reactions with Dragendorff reagent;Farnsworth;Lloydia,1962
5. Spot Tests in Organic Analysis;Feigl,1956