The structure functions of real and virtual photons are derived from cross
section measurements of the reaction e(+)e(-)--> e(+)e(-)+ hadrons at LEP.
The reaction is studied at root s= 91GeV with the L3 detector. One of the f
inal state electrons is detected at a large angle relative to the beam dire
ction, leading to Q(2) values between 40 GeV2 and 500 GeV2 The other final
state electron is either undetected or it is detected at a four-momentum tr
ansfer squared P-2 between 1 GeV2 and 8 GeV2. These measurements are compar
ed with predictions of the Quark Parton Model and other QCD based models. (
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