1. Quantitative determination of morphine in opium by gas-liquid chromatography;Brochmann-Hanssen;J. Pharm. Sci.,1963
2. Unified analysis of opium for alkaloids;Fultan;United Nations Secretariat Document, ST/SOA/SER.K/34,1954
3. Partition chromatographic-gravimetric assay of opium;Smith;J. Ass. Anal. Chem.,1972
4. Opium alkaloids. XII. Quantitative determination of morphine in opium by isotope dilution;Brochmann-Hanssen;J. Pharm. Sci.,1972
5. Paper chromatography in checking the determination of morphine in opium;Buechi;Pharm. Acta Helv.,1961