Horak, Ivan Gerard; Nyangiwe, Nkululeko; De Matos, Carlos Antonio; Das Neves, Luis Carlos Bernardo G.(Agricultural Research Council, ARC-OVI and the University of Pretoria, 2009-02)
Gallivan, Gordon J.; Spickett, Andrea; Heyne, Heloise; Spickett, Arthur M.; Horak, Ivan Gerard(Agricultural Research Council, ARC-OVI and the University of Pretoria, 2011)