I-Pullback sisilungiso sexeshana esihlala sisenzeka emva kwentshukumo ebalulekileyo. Khumbula ukuba i-pullbacks ayiqinisekisi ukuqhubeka kwaye inokujika ngokulula ibe yintshukumo ebuyela umva. Nangona kunjalo, indibaniselwano ye-pullback kunye nezinye izixhobo zobugcisa kunye nobuchule kunokubonelela ngamathuba amakhulu okurhweba. Kukho iindidi ezimbini zomlenze wesenzo sexabiso…