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The language is considered to have three dialects: Nyambwa (Cinyambwa or West Gogo), spoken to the west of Dodoma and in Manyoni; Nyaugogo (Cinyaugogo or Central Gogo), spoken in the environs of Dodoma; and Tumba (Citumba or East Gogo), spoken to the east. The Gogo group is grouped with Kagulu, which has a 56% lexical similarity with Gogo proper. Gogo has about 50% lexical similarity with Hehe and Sangu (both Bena–Kinga languages (G.60), 48% with Kimbu and 45% with Nilamba. These last two are both in Guthrie's Zone F.
Rugemalira, Josephat M. (2009). Cigogo, Kamusi ya Kigogo-Kiswahili-Kiingereza / Kiingereza-Kigogo, na Kiswahili-Kigogo / Gogo-Swahili-English, English-Gogo, and Swahili-Gogo Dictionary. ISBN9987-691-25-0.
Nurse, Derek and S. M. Mazengo. 1979. Gogo. African languages/Langues africaines 5. 70–76, 101–104.