Abstract
We discuss two types of contributions to hadronic form factors in QCD: hard gluon exchange and soft wave function overlap. Within the QCD sum rule approach, the hard contribution has strong numeric suppression by factor (α_s/π) ~ 0.1 for each exchange. For this reason, the soft contribution dominates at accessible momentum transfers. The ``humpy'' distribution amplitudes used to enhance hard terms cannot be derived from QCD sum rules in a self-consistent way. The estimates of soft terms obtained within the local quark-hadronic duality approach in all cases are close to existing data, providing an experimental evidence that hard terms are small.
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