M. Githua, A. Hassanali, J. Keriko, M. Ndungu, G. Murilla, and G. Nyagah, “NEW ANTITRYPANOSOMAL TETRANOTRITERPENOIDS FROM AZADIRACHTA INDICA”, Afr J Tradit Complement Altern Med, vol. 7, no. 3, pp. 207–213, Feb. 2010.