00842cam a2200229 i 4500 ocn122316271 900401s1973 sa F afr d 9780869650899 0869650890 afr xx 370.193 20 Roos, Willem Lodewyk. 'n Verkenningstudie ten opsigte van die probleem van onderprestasie op standerd ses-vlak / W.L. Roos. [Pretoria] : Instituut vir Mannekragnavorsing, 1973. 76 p. Verslae / Raad vir Geesteswetenskaplike Navorsing. InstituutMannekragnavorsing ; nr. MT-12 Ability Testing. Institute for Manpower Research (Human Sciences Research Council) Verslag (Institute for Manpower Research (South Africa : 1968-1979)) ; MT-12. 0 4099 4099 0 0 ddc 0 0 DAPA DAPA 2013-07-25 0 370.19 ROO APA058943 2013-07-25 1 2013-07-25