A Study of Charm Hadron Production in Z0 -> cc(bar)                            
and Z0 -> bb(bar) decays at LEP                                                
  
The production rates of D^0, D^+, D^+_s and Lambda_c^+ in hadronic Z0 decays   
have been measured using the complete OPAL LEP1 dataset. Production in         
Z0 --> bb and Z0 -->cc decays is separated using the momentum and decay length 
of the charm hadrons. The results are used to determine                        
R_c = Gamma_c bar c/Gamma_had and the charm hadron multiplicity in b           
hadron decays.                                                                 
  
 Parallel session :7                   
 Plenary  session :3