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Smith, Jason A.; Molesworth, Peter P.; Hyland, Christopher J. T.; Ryan, John H. (2011-01-01), Gribble, Gordon; Joule, John A. (ed.), Chapter 7 - Seven-Membered Rings, Progress in Heterocyclic Chemistry (dalam bahasa Inggris), vol.22, Elsevier, hlm.491–536, doi:10.1016/S0959-6380(11)22016-6, ISBN9780080966854, diakses tanggal 2023-01-05