W. C. Shawa,
Manganese removal in Kitwe Water Works, vol. no. 13. Tampere, Finland: Tampere University of Technology, 1981, p. 47 p. + 6 p. annexes : fig., tab.
W. R. C. Kayombo,
Pipe materials in transmission mains, vol. no. 6. Tampere, Finland: Tampere University of Technology, Dept. of Civil Engineering, 1981, p. iii, 65 p. : fig., tab.