by Hartley, L.M., Donnelly, C.A., Garnett, G.P.
Published in Transactions of the Royal Society of Tropical Medicine and Hygiene (01.07.2002)

by Gordon, D.S., Halliwell, R.F., Hartley, L.M., Heeger, E.E., Horobin, J.M., Murch, R.D., Pocock, J.M., Thomas, M.L.
Published in International journal of information management (01.06.1991)