Fragmentation into K+- in e+e- annihilations:
Inclusive cross sections (1/sigma_had)(dsigma/dx), with x=p/p_beam.
The indicated errors are statistical and systematic errors added in
quadrature.
triangles: rate at sqrt{s}=9.98 GeV; an overall uncertainty of 1.8%:
           ARGUS Collab., H. Albrecht et al., Z. Phys. C44, 547 (1989).
squares:   rate at sqrt{s}=29 GeV:
           TPC Collab., H. Aihara et al., Phys. Rev. Lett. 61, 1263 (1988).
circles:   rate for hadronic decays of the Z at sqrt{s}=91.2 GeV:
           ALEPH  Collab., D. Buskulic et al., Z. Phys. C66, 355 (1995);
           DELPHI Collab., P. Abreu et al., Eur. Phys. J. C5, 585 (1998);
           OPAL   Collab., R. Akers et al., Z. Phys., C63, 181 (1994);
           SLD    Collab., K. Abe et al., Phys. Rev. D69, 072003 (2004).
(Courtesy of O. Biebel, LMU, Munich, 2005).