CERN-LHC. Decays of b hadrons into final states containing a D0 meson and a muon are used to measure the bbbar production cross-section. The average cross-section to produce b-flavoured or bbar-flavoured hadrons is measured in different pseudorapidity intervals over the entire range of pT assuming the LEP (and Tevatron) fractions for fragmentation into b-flavoured hadrons. Note that since the publication of this paper, LHCb measurements of the b-fractions have shown that the Tevatron b-fractions are correct (see http://arxiv.org/abs/1111.2357) and therefore should be used in preference to the LEP ones. This record lists both for completeness. ; Other ; The cross section for b-flavoured hadrons (HADRON/B) over the pseudorapidity range 2.0-6.0 in proton-proton collisions at a centre-of-mass energy of 7 TeV. Cross sections are shown using fragmentation fractions both from LEP and from the Tevatron. See comment above regarding this latter point.