The Behavior of Form Factors of Nucleon Resonances and Quark-Hadron   Duality
  A behavior of the nucleon structure functions in the resonance region is investigated. Expressions for resonance production form factors, dependent on photon virtuality $Q^2$, which have correct threshold behavior and take into account available data on resonance decays, are obtained. Contributions of resonances to nucleon structure functions are calculated. Obtained expressions are used to investigate the quark-hadron duality in the electron-nucleon scattering processes with the structure function $F_2$ as an example. 
V.V. Davidovsky, B.V. Struminsky