Krogh, L. (1993) “Dryland agriculture - strategies for sustainability. R.P. Singh, J.F. Parr, & B.A. Stewart (eds.). - (Advances in soil science; 13).”, Geografisk Tidsskrift, 93. Tilgængelig hos: https://tidsskrift.dk/geografisktidsskrift/article/view/42248 (Set: 24november2020).