SUBROUTINE PERIOD (IVPSOL,N,M,T,X,P,EPS,FM,NRW,RW,NIW,IW,ICALL)
C*    Begin Prologue PERIOD
      EXTERNAL IVPSOL
      DOUBLE PRECISION EPS,P,T(M),X(N,M),FM(N,2),RW(NRW)
      INTEGER IW(NIW),ICALL(8)
C
C---------------------------------------------------------------------
C
C*  Title
C
C    (Period)ic Solution of Nonlinear Ordinary Differential Equations
C
C*  Written by        P. Deuflhard, R. Winzen
C*  Purpose           Solution of nonlinear two-point boundary value
C                     problems with period solutions of an unknown
C                     period length 
C*  Method            Local Nonlinear two-point Boundary Value
C                     Problems solver (Multiple shooting approach)
C*  Category          I1b3 - Differential and integral equations
C                            Eigenvalue problems
C*  Keywords          Nonlinear boundary value problems, Multiple
C                     shooting, Newton methods, Period solutions
C*  Version           0.5 (Test Version)
C*  Revision          July 1984
C*  Latest Change     January 1991
C*  Library           CodeLib
C*  Code              Fortran 77, Double Precision
C*  Environment       Standard Fortran 77 environment on PC's,
C                     workstations and hosts.
C*  Copyright     (c) Konrad-Zuse-Zentrum fuer
C                     Informationstechnik Berlin (ZIB)
C                     Takustrasse 7, D-14195 Berlin-Dahlem
C                     phone : + 49/30/84185-0
C                     fax   : + 49/30/84185-125
C*  Contact           Lutz Weimann
C                     ZIB, Division Scientific Computing, 
C                          Department Scientific Software
C                     phone : + 49/30/84185-185
C                     fax   : + 49/30/84185-107
C                     e-mail: weimann@zib.de

The distribution contains the following files:

  period.f         the solver
  linalg_period.f  linear algebra (deccon,solcon)
  period.nrm       output of the example
  main_period.f    main example program
  makefile         makefile for compilation
  readme           this file
  zibconst.f       machine dependant constants
  zibsec.f         machine dependant timing routine