Cannabis L.
Cannabis is a monospecific genus native to Central Asia. Its single species, Cannabis sativa (Indian hemp), is widely cultivated, mainly as a psychotropic drug or for fiber (less commonly also as an oil seed, as bird seed, etc.).
References
(see also references under C. sativa)
Abel E.L. (1980) Marihuana: the first twelve thousand years. New York: London, Plenum Press: xi + 289p.
Anderson L.C. (1980) Leaf variation among Cannabis species from a controlled garden. Bot. Mus. Leafl. Harvard Univ. 28(1): 61-69. [available online at: https://www.biodiversitylibrary.org/page/7468476#page/79/mode/1up]
Du Toit B.M. (1981) Cannabis in Africa: a survey of its distribution in Africa, and a study of cannabis use and users in multi-etnic South Africa. Rotterdam: A.A. Balkema for African Studies Center, University of Florida: xv + 512p.
Emboden W.A. (1975) Cannabis-a polytypic genus. Econ. Bot. 28: 304-310.
Emboden W.A. (1977) A taxonomy for Cannabis. Taxon 26(1): 110.
Emboden W.A. (1981) The genus Cannabis and correct use of taxonomic categories. J. Psychoact. Drugs 13(1): 15-22.
Merzouki A., Casares Porcel M. & Molero Mesa J. (1996) A morphological achene study of some "species" of Cannabis: a taxonomic approach. Arch. Geobot. 2(1): 65-71.
Pillay M. & Kenny S.T. (2006) Structural organization of the nuclear ribosomal RNA genes in Cannabis and Humulus (Cannabaceae). Pl. Syst. Evol. 258: 97-105.
Shao H. & Clarke R.C. (1996) Taxonomic studies of Cannabis in China. J. Int. Hemp Assoc. 3(2): 55-60. [available online at: https://www.researchgate.net/profile/Robert_Clarke12/publication/2886762...
Small E. (1977) Nomenclatural nonsense and legal marijuana plants. Bull. Pac. Trop. Bot. Gard. 7(1): 1-6.
Small E. (1979) The species problem in Cannabis: Science and semantics. Toronto, Corpus Publications: 374p.
Small E. (1997) Cannabaceae. In: Flora of North America Editorial Committee (eds.), Flora of North America, vol. 3. Oxford University Press, New York-Oxford: 381-387. [available online at: http://www.efloras.org/florataxon.aspx?flora_id=1&taxon_id=105522]
Small E. (2011) Morphological variation of achenes of Cannabis. Canadian Journal of Botany 53(10): 978-987.
Small E. & Cronquist A. (1976) A practical and natural taxonomy for Cannabis. Taxon 25: 405-435.
Wilmot Dear C.M. (1999) FSA contributions: 14. Cannabaceae. Bothalia 29(2): 249-252. [available online at: https://abcjournal.org/index.php/ABC/article/viewFile/595/539]