Posey BL, Kimble SN (1984). "High-performance liquid chromatographic study of codeine, norcodeine, and morphine as indicators of codeine ingestion". Journal of Analytical Toxicology. 8 (2): 68–74. doi:10.1093/jat/8.2.68. PMID6716978.
Fraser HF, Isbell H, Vanhorn GD (June 1960). "Human pharmacology and addiction liability of norcodeine". The Journal of Pharmacology and Experimental Therapeutics. 129: 172–7. PMID13824628.
Posey BL, Kimble SN (1984). "High-performance liquid chromatographic study of codeine, norcodeine, and morphine as indicators of codeine ingestion". Journal of Analytical Toxicology. 8 (2): 68–74. doi:10.1093/jat/8.2.68. PMID6716978.