  A method to calculate heavy flavor visible-level cross sections at
Next-to-Leading Order (NLO) in Quantum Chromodynamics (QCD), based on an
interface of the FMNR program to PYTHIA, is described. It uses the NLO
prediction at quark level provided by FMNR, with a statistical reduction
procedure (REDSTAT) that allows a link to PYTHIA 6.2 to be made, from where the
description of the full hadron fragmentation and decay chain is obtained. The
method is applied to ep -> b bbar X -> D* mu X and mu+ mu- X final states at
HERA. Comparisons of the data and NLO cross sections at visible and b-quark
level were found to be consistent.
