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Nutt, D.; King, L.A.; Saulsbury, C.; Blakemore, Colin (March 2007). "Development of a rational scale to assess the harm of drugs of potential misuse". Lancet. 369 (9566): 1047–53. doi:10.1016/S0140-6736(07)60464-4. PMID17382831. S2CID5903121.
Manghi, Rita Annoni; Broers, Barbara; Khan, Riaz; Benguettat, Djamel; Khazaal, Yasser; Zullino, Daniele Fabio (2009). "Haight-Ashbury Free Medical Clinic". Journal of Psychoactive Drugs. 41 (1): 1–10. doi:10.1080/02791072.2009.10400669. PMID19455904. S2CID30637165.
Nutt, D; King, LA; Saulsbury, W; Blakemore, C (24 March 2007). "Development of a rational scale to assess the harm of drugs of potential misuse". Lancet. 369 (9566): 1047–53. doi:10.1016/s0140-6736(07)60464-4. PMID17382831. S2CID5903121.
Giannini, A.J.; Castellani, S. (July 1982). "A manic-like psychosis due to khat (Catha edulis Forsk.)". Journal of Toxicology. Clinical Toxicology. 19 (5): 455–59. doi:10.3109/15563658208992500. PMID7175990.
Al-Motarreb, A. L.; Broadley, K. J. (October–December 2003). "Coronary and aortic vasoconstriction by cathinone, the active constituent of khat". Autonomic & Autacoid Pharmacology. 23 (5–6): 319–26. doi:10.1111/j.1474-8673.2004.00303.x. PMID15255816.
Ché-Ross, Raimy (2000). "Munshi Abdullah's voyage to Mecca: A preliminary introduction and annotated translation". Indonesia and the Malay World. 28 (81): 173–213. doi:10.1080/713672763. S2CID162579224.
"Protected Trees"(PDF). Department of Water Affairs and Forestry, Republic of South Africa. 3 May 2013. Archived from the original(PDF) on 5 July 2010.
Nutt, D.; King, L.A.; Saulsbury, C.; Blakemore, Colin (March 2007). "Development of a rational scale to assess the harm of drugs of potential misuse". Lancet. 369 (9566): 1047–53. doi:10.1016/S0140-6736(07)60464-4. PMID17382831. S2CID5903121.
Manghi, Rita Annoni; Broers, Barbara; Khan, Riaz; Benguettat, Djamel; Khazaal, Yasser; Zullino, Daniele Fabio (2009). "Haight-Ashbury Free Medical Clinic". Journal of Psychoactive Drugs. 41 (1): 1–10. doi:10.1080/02791072.2009.10400669. PMID19455904. S2CID30637165.
Nutt, D; King, LA; Saulsbury, W; Blakemore, C (24 March 2007). "Development of a rational scale to assess the harm of drugs of potential misuse". Lancet. 369 (9566): 1047–53. doi:10.1016/s0140-6736(07)60464-4. PMID17382831. S2CID5903121.
Giannini, A.J.; Castellani, S. (July 1982). "A manic-like psychosis due to khat (Catha edulis Forsk.)". Journal of Toxicology. Clinical Toxicology. 19 (5): 455–59. doi:10.3109/15563658208992500. PMID7175990.
Al-Motarreb, A. L.; Broadley, K. J. (October–December 2003). "Coronary and aortic vasoconstriction by cathinone, the active constituent of khat". Autonomic & Autacoid Pharmacology. 23 (5–6): 319–26. doi:10.1111/j.1474-8673.2004.00303.x. PMID15255816.
Nutt, D.; King, L.A.; Saulsbury, C.; Blakemore, Colin (March 2007). "Development of a rational scale to assess the harm of drugs of potential misuse". Lancet. 369 (9566): 1047–53. doi:10.1016/S0140-6736(07)60464-4. PMID17382831. S2CID5903121.
Manghi, Rita Annoni; Broers, Barbara; Khan, Riaz; Benguettat, Djamel; Khazaal, Yasser; Zullino, Daniele Fabio (2009). "Haight-Ashbury Free Medical Clinic". Journal of Psychoactive Drugs. 41 (1): 1–10. doi:10.1080/02791072.2009.10400669. PMID19455904. S2CID30637165.
Nutt, D; King, LA; Saulsbury, W; Blakemore, C (24 March 2007). "Development of a rational scale to assess the harm of drugs of potential misuse". Lancet. 369 (9566): 1047–53. doi:10.1016/s0140-6736(07)60464-4. PMID17382831. S2CID5903121.
Ché-Ross, Raimy (2000). "Munshi Abdullah's voyage to Mecca: A preliminary introduction and annotated translation". Indonesia and the Malay World. 28 (81): 173–213. doi:10.1080/713672763. S2CID162579224.
"Protected Trees"(PDF). Department of Water Affairs and Forestry, Republic of South Africa. 3 May 2013. Archived from the original(PDF) on 5 July 2010.
Zecharia Madar, "The Khat Phenomenon in Yemen and the Dangers it Poses", in: Ascending the Palm Tree – An Anthology of the Yemenite Jewish Heritage, Rachel Yedid & Danny Bar-Maoz (ed.), E'ele BeTamar: Rehovot 2018, p. 144 OCLC1041776317
Madar, Zecharia (2018), "The Khat Phenomenon in Yemen, and the Dangers it Poses", in Rachel Yedid; Danny Bar-Maoz (eds.), Ascending the Palm Tree: An Anthology of the Yemenite Jewish Heritage, Rehovot: E'ele BeTamar, p. 147, OCLC1041776317