CKM Matrix from Leptoquark-Quark Mixing in a String Model
  We investigate a scenario in which the CKM matrix arises from leptoquark--down quark mixing in a particular standard--like superstring model. We find that for some choices of F and D flat directions realistic quark mixing can be obtained without any phenomenological problems. This scenario predicts a symmetric (in absolute value) CKM matrix. 
Edi Halyo