Extracted from dpcon61.f

C  PCON61 is version 6.1 of PITCON, the University of Pittsburgh continuation
C  program.
C
C  PITCON was written by
C
C    Professor Werner C Rheinboldt and John Burkardt,
C    Department of Mathematics and Statistics
C    University of Pittsburgh,
C    Pittsburgh, Pennsylvania, 15260, USA. 
C  H. References
C
C
C  1.
C  Werner Rheinboldt,
C  Solution Field of Nonlinear Equations and Continuation Methods,
C  SIAM Journal of Numerical Analysis,
C  Volume 17, 1980, pages 221-237.
C
C  2.
C  Cor den Heijer and Werner Rheinboldt,
C  On Steplength Algorithms for a Class of Continuation Methods,
C  SIAM Journal of Numerical Analysis,
C  Volume 18, 1981, pages 925-947.
C
C  3.
C  Werner Rheinboldt,
C  Numerical Analysis of Parametrized Nonlinear Equations
C  John Wiley and Sons, New York, 1986
C
C  4.
C  Werner Rheinboldt and John Burkardt,
C  A Locally Parameterized Continuation Process,
C  ACM Transactions on Mathematical Software,
C  Volume 9, Number 2, June 1983, pages 215-235.
C
C  5.
C  Werner Rheinboldt and John Burkardt,
C  Algorithm 596, A Program for a Locally Parameterized Continuation Process,
C  ACM Transactions on Mathematical Software,
C  Volume 9, Number 2, June 1983, Pages 236-241. 
