Campbell, D. (1922). In the heart of Bantuland: A record of twenty-nine years' pioneering in Central Africa among the Bantu peoples, with a description of their habits, customs, secret societies and languages. Seeley, Service & Co..

Campbell, Dugald. In the Heart of Bantuland: A Record of Twenty-nine Years' Pioneering in Central Africa Among the Bantu Peoples, with a Description of Their Habits, Customs, Secret Societies and Languages. London: Seeley, Service & Co., 1922.

Campbell, Dugald. In the Heart of Bantuland: A Record of Twenty-nine Years' Pioneering in Central Africa Among the Bantu Peoples, with a Description of Their Habits, Customs, Secret Societies and Languages. Seeley, Service & Co., 1922.