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   Acknowledgments                                                               
                                                                                 
   JPH and FR would like to thank Gautam Altekar, Andrea Betancourt, Jon         
   Bollback, Barry Hall, Jimmy McGuire, Rasmus Nielsen, David Swofford,          
   Johan Nylander, Mikael Thollesson, and Derrick Zwickl for help during the     
   development of this program. Gautam Altekar, especially, was instrumental     
   in getting the parallel version of the program working.                       
                                                                                 
   Our wives -- Edna Huelsenbeck and Eva Ronquist -- showed extraordinary        
   patience with us while we spent many late nights programming.                 
                                                                                 
   JPH was supported by NSF grants DEB-007540 and MCB-0075404 and a Wenner-      
   Gren scholarship while writing this program. FR was supported by a grant      
   from the Swedish Natural Science Research Council.                            
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