Forskning tyder på, at nærtstående slægter som ''Fortunella'' ([[kumquat]]), ''Poncirus'' ([[dværgcitron]]) og muligvis de australske slægter ''Microcitrus'' og ''Eremocitrus'',<sup>[[:en:Citrus taxonomy|en]]</sup> bør høre hjemme i ''Citrus'', hvortil de fleste botanikere henfører dem til i dag.<ref>E. Nicolosi, Z.N. Deng, A. Gentile, S. La Malfa, G. Continella og E. Tribulato: ''"Citrus" phylogeny and genetic origin of important species as investigated by molecular markers'' i ''Theoretical and Applied Genetics'', 2000 + E. Freitas de Araújo. L. de Queiroz, L. Paganucci og M.A. Machado: ''What is "Citrus"? Taxonomic implications from a study of cp-DNA evolution in the tribe Citreae (Rutaceae subfamily Aurantioideae) '' i ''Organisms Diversity & Evolution'', 2003</ref><ref>https://www.researchgate.net/figure/Genetic-Origin-of-the-Citrus-Accessions-Considered-in-This-Study-Maternal-and-paternal_fig1_329816118/amp</ref><ref> https://www.chandigarhayurvedcentre.com/blog/tangerine-kinnow/</ref><ref> https://www.researchgate.net/figure/Admixture-proportion-and-citrus-genealogy-a-Allelic-proportion-of-five-progenitor_fig2_322991573/amp</ref><ref> http://www.botanicalaccuracy.com/2014/06/the-species-names-of-citrus-sweet-sour.html?m=1</ref><ref> https://johnhawks.net/weblog/reviews/genomics/agricultural/citrus-fruits-origins-2018.html</ref><ref> https://blogs.reading.ac.uk/crg/adventbotany-2019-day-1-clementine-satsuma-tangerine-whats-the-difference/img-3_books-openedition-org_pcjb_docannexe_image_2169_img-3/</ref><ref> http://tropical.theferns.info/viewtropical.php?id=Citrus+deliciosa</ref><ref> https://citrusvariety.ucr.edu/citrus/kishu.html</ref>
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