1997 IUCN red list of threatened plants (1997)

Biosphere Reserves, Compilation 4, October 1986: programme on man and the biosphere (MAB) (1986)

British Central Africa; an attempt to give some account of a portion of the territories under British influence north of the Zambesi - Johnston, Harry, 1858 -1927 (Methuen & co, 1906)

Bulletin - East Africa Natural History Society. (East Africa Natural History Society, 1984)

Bulletin of miscellaneous information - Royal Botanic Gardens, Kew. (H.M. Stationery Office, 1907)

Bulletin of miscellaneous information - Royal Botanic Gardens, Kew. (H.M. Stationery Office, 1907)

Le Coelastrum proboscideum Bohl. Étude de planetologie expérimentale suivie d'une revision des Coelastrum de la Suisse - Rayss, Tscharna, 1891 - (K.J. Wyss, 1915)

Flora der gefürsteten Grafshaft Tirol, des Landes Vorarlberg und des Fürstenthumes Liechtenstein - Dalla Torre, K. W. von (Karl Wilhelm), 1850 -1928 (Verlag der Wagner'-schen Universitäts-Buchhandlung, 1904)

IUCN Directory of Afrotropical Protected Areas (1987)

IUCN Directory of Afrotropical Protected Areas (1987)

Lake Nyasa climatic region : floristic checklist - Gereau, Roy E., (Missouri Botanical Garden, 2012)

Memoirs of the New York Botanical Garden - New York Botanical Garden (The Garden, 1953)

Memoirs of the New York Botanical Garden - New York Botanical Garden (The Garden, 1953)