We make an analysis of the Gribov-Lipatov relation using the phenomenological forms of the structure functionF₂^ep. Our analysis indicate breakdown of the relation at PETRA energies. Plausible reasons of the breakdown of Gribov-Lipatov relation are discussed together with its phenomenological form.

We study the inclusivee⁺e⁻ processes at the PETRA energy range within QCD and a fixed point theory using the phenomenological Gribov-Lipatov inequality suggested in an earlier analysis. Theoretical justification is provided within QCD and its possible implication in hadronization is discussed.

We derive an approximate formula for the quark mass in ξ-formalism. Using the QCD-based form of structure function, we analyse the SLAC-MIT data to estimate the experimentally allowed ranges of quark mass. The possible variation of our results with QCD cut-off parameter, gluon distribution, hard intrinsic charm component of the proton wavefunction and the higher twist effects are also discussed.