Catalogue of the African plants - British Museum (Natural History). Department of Botany. (Printed by order of the Trustees, 1896)

Flora of tropical Africa - Oliver, Daniel, 1830 -1916 (L. Reeve and co, 1906)

Flora of tropical Africa - Oliver, Daniel, 1830 -1916 (L. Reeve and co, 1906)

Index Kewensis. names of seed-bearing plants at the rank of family and below published between January 1991 and the end of 1995 with some omissions from earlier years Supplement twenty - Royal Botanic Gardens, Kew. (Royal Botanic Gardens, Kew)

Just's Botanischer Jahresbericht - Just, Johann Leopold, 1841 -1891 (Gebruder Borntraeger, 1898)

Die Vegetation der Erde :Sammlung pflanzengeographischer Monographien - Engler, Adolf, 1844 -1930 (W. Engelmann, 1910)