Acocks, J.P.H.: Veld types of South Africa. Mem. Bot. Surv. S. Afr. 28, 1–192 (1953)Google Scholar
Agric. J. Union S.A.: Is South Africa drying up? 4, 662–666; 6, 693–694, 1027–1029; 7, 47–60, 113–114, 150–154, 256–261, 243–424, 523–538, 732–739, 894–898; 8, 107–113, 262–265 (1912–1914)
Alexander, W.J.R.: Personal communication. (1978)
Barber, F.H.: Is South Africa drying up? Agric. J. Cape H.G. 86, 167–170 (1910)Google Scholar
Bayer, A.W.: The ecology of grasslands. In: Meredith, D.: The grasses and pastures of South Africa. pp. 539–550. Central News Agency, Johannesburg 1955.Google Scholar
Donaldson, C.H., Kelk, D.M.: An investigation of the veld problems of the Molopo area: 1 Early findings. Proc. Grassl. Soc. S. Afr. 5, 50–57 (1970)Google Scholar
Dregne, H.E.: Status of desertification in the hot arid lands. United Nations Conference on Desertification, Nairobi, Kenya: A/Conf. 74/31, pp. 4–6, 1977.
Dyer, T.G.J.: The assignment of rainfall stations into homogeneous groups: an application of principal components analysis. Quart. J. R. Met. Soc. 101, 1005–1013 (1975)Google Scholar
Dyer, T.G.J.: On the components of time series: the removal of spatial dependence. Quart. J. R. Met. Soc. 102, 157–165 (1976a)Google Scholar
Dyer, T.G.J.: Meridional interactions between rainfall and surface pressure. Nature 264, 48–49 (1976b)Google Scholar
Dyer, T.G.J., Tyson, P.D.: Extended forecasts of above- and below-normal rainfall over South Africa. Jour. Appl. Meteorol. 16, 145–147 (1977)Google Scholar
Dyer, T.G.J., Tyson, P.D.: Inter-hemispheric associations in the year-to-year variation of major components of the general circulation of the atmosphere. S. A. J. Sc. 74, 325–328 (1978)Google Scholar
Hare, F.K.: Climate and desertification. U.N.C.O.D. A/Conf. 74/5, pp. 140, 1977.Google Scholar
Hutchins, D.E.: Cycles of drought and good seasons in SOuth Africa. Times Office, Wynberg 1888.Google Scholar
Jenkinson, A.F.: A powerful elementary method of spectral analysis for use with monthly, seasonal, or annual meteorological time series. Met. 0 13, Branch Memo. No. 57, Bracknell (1976)
Kokot, D.F.: An investigation into the evidence bearing on the recent climatic changes over Southern Africa. Union of S.A., Irrigation Dept. Memoir. Govt. Printer, Pretoria 1948Google Scholar
Mabbutt, J.A.: Desertification of Australia in its global context. Search 9, 252–256 (1978)Google Scholar
Lesotho: 1970 Census of Agriculture Report. Bureau of Statistics, Maseru, pp. 77–78 (1970)Google Scholar
Phillips, J.: Deterioration in the vegetation of the Union of South Africa, and how this may be controlled. S. Afr. J. Sc. 35, 476–484 (1938)Google Scholar
Schwarz, E.H.L.: The progressive desiccation of Africa: the cause and the remedy. S. Afr. J. Sc. 15, 139–190 (1919)Google Scholar
Schwarz, E.H.L.: Kalahari scheme as the solution of the Sout African drought problem. S. Afr. J. Sc. 20, 208–222 (1923)Google Scholar
Shantz, H.L., Turner, B.L.: Photographic documentation of vegetational changes in Africa over a third of a century. Univ. of Arizona 1958.
South Africa (Union of): Desert encroachment committee. Report. Government Printer, Pretoria, U.G. 59 of 1951, 27 pp., chairman C.R. van der Merwe 1951.Google Scholar
South Africa (Republic of): Commission of enquiry into Agriculture Reports. Interim Report, R.P. 61 of 1968, 100 pp., chairman M.D. Marais; second report, R.P. 84 of 1970, 234 pp., chairman M.D. Marais; third (final) report, R.P. 19 of 1972, 221 pp., chairman S.J. du Plessis 1968–1972.
Talbot, W.J.: Land utilization in the arid regions of Southern Africa. Part I: South Africa. Arid Zone Res. 17, 299–331 (1961)Google Scholar
Theron, M.J., Mathews, V.L., Neethling, P.J.: The economic importance of the weather and weather services to the South African agricultural sector — a Delphi survey. C.S.I.R. Research Report 321, 134 pp., 1973.
Tidmarsh, C.E.M.: Pasture research in South Africa. Proc. Grassl. Soc. S. Afr. 1, 21–26 (1966)Google Scholar
Tyson, P.D.: Rainfall fluctuations over South Africa during the period of meteorological record. Paper presented to the International Convention: Water for the future. Pretoria 1970.
Tyson, P.D.: Spatial variation of rainfall spectra in South Africa. Ann. Ass. Am. Geog. 61, 711–720 (1971)Google Scholar
Tyson, P.D.: Rainfall changes over South Africa during the period of meteorological record. In Biography and Ecology of Southern Africa. M.J.A. Werger (Ed.). W. Junk, The Hague, pp. 55–69, 1978.Google Scholar
Tyson, P.D.: Temporal and spatial variation of rainfall anomalies in Africa south of latitude 22° during the period of meteorological record. Climatic Change 2, 363–371 (1980)Google Scholar
Tyson, P.D.: Atmospheric circulation changes and the occurence of extended wet and dry spells over southern Africa. J. Climatol. 1 (in press) (1981)
Tyson, P.D., Dyer, T.G.J.: Mean fluctuations of precipitation in summer rainfall region of South Africa. S. Afr. Geog. J. 57, 104–110 (1975)Google Scholar
Tyson, P.D., Dyer, T.G.J.: The predicted above-normal rains of the seventies and the likelihood of drought in the eighties. S.A.J. Sc. 74, 372–377 (1978)Google Scholar
Tyson, P.D., Dyer, T.G.J., Mametse, M.N.: Secular changes in South African rainfall: 1880–1972. Quart. J. R. Met. Soc. 101, 817–833 (1975)Google Scholar
UNCOD: Report of the UN Conference on Desertification, Nairobi, Kenya: A/Conf. 74/31 pp. 4–6, 1977.
Vorster, J.H.: Trends in long range rainfall records in South Africa. S. Afr. Geog. J. 39, 61–66 (1957)Google Scholar
Werger, M.J.A.: Phytosociology of the Upper Orange River valley. V & R. Pretoria, 222 pp., 1973.
Wilcocks, J.R.N.: Desert encroachment in South Africa. Unpublished M. A. dissertation, University of the Witwatersrand, Johannesburg, 347 pp., 1977.Google Scholar
Wilken, G.C.: Agroclimatic hazards and risk perception in Lesotho: a preliminary view. Paper presented at the I.G.U. Regional Conference, Ibadan, Nigeria July 1978, 4 pp. (mimeo), 1978.