The cross section for b (b) over bar production in 800 GeV/c pN interactions has been measured in Fermilab, experiment E771 to be 43(-17)(+27)(stat)(-7)(+7)(syst) nb per nucleon from the observation of events in which both the b and the (b) over bar decay semimuonically or a B decays into a J/psi followed by J/psi --> mu(+)mu(-). [S0031-9007(98)07987-3].
