Burnett, Duncan, Farrell, Graham and Kiiru, Mary (2002) Strategies for the development of a competitive pyrethrum-based pesticide sector in Kenya. Final report (NRI report no. 2695). Technical Report. Natural Resources Institute, Chatham, UK.

Farrell, Graham (1998) Towards the management of Ustilago kamerunensis H Sydow and Sydow, a smut pathogen of napier grass (Pennisetum purpureum Schum.) in Kenya. PhD thesis, University of Greenwich.