  A program to simulate the production of heavy quarks through the boson-gluon
fusion process in $e^{\pm}p$ collisions is presented. The full electro\-weak
structure of the electron--gluon interaction is taken into account as well as
the masses of the produced heavy quarks. Higher order QCD radiation is treated
using initial and final state parton showers, and hadronization is performed
using the Lund string model. Physics and programming aspects are described in
this manual.
