J.D. Deans, O.M. Ali, D.K. Lindley, and H.O.A. Nour, “RHIZOBIAL NODULATION OF <em>ACACIA</em> TREE SPECIES IN SUDAN: SOIL INOCULUM POTENTIAL AND EFFECTS OF PEAT”, JTFS, vol. 6, no. 1, pp. 56–64, Sep. 1993.