James, Gilad, PhD, "Introduction to Guinea-Bissau", Gilad James Mystery School, p. 41, ISBN9788770043847[2] (retrieved 9 November 2023)
Havik, Philip J., "Silences and Soundbites: The Gendered Dynamics of Trade and Brokerage in the Pre-colonial Guinea Bissau Region" (Volume 2 of Modernity and belonging), LIT Verlag Münster (2004), p. 146, ISBN9783825877095. [3] (retrieved 9 November 2023)