Higher-order correlations have been observed as particle-density fluctuations. Approximate scaling with improving resolution provides evidence for a self-similar correlation effect. Quantum-Chromodynamics branching is a good candidate for a dynamical explanation of these correlations in e⁺e^- collisions at CERN/LEP and, as expected, also of those in pp collisions at future CERN/LHC energies. However, also other sources such as identical-particle Bose--Einstein interference effects contribute.

PACS numbers: 12.38.Lg, 12.38.Qk, 13.66.Bc, 13.85.Hd, 13.87.Fh, 13.90.+i