int rtbp (int kv, int nv[], void *prm, double t, double x[], double f[]);
int rkf78 (int n, int kv, int nv[], void *prm,
      int (*camp)(int,int[],void *,double,double [],double []),
      double *t, double x[], double *h,
      double hmin, double hmax, double tol, double *eerr, int ivb);
int proptraj_vella (double mu, int nt, double c, int isgn, double x,
      double *u, double *du, double pmax, FILE *fp);
void rva2z (double mu, double r0, double v0, double csa, double sna,
            double *z);
void proptraj (double mu, int nt, double *z0, double *zf, double *du,
      double pmax, FILE *fp);
double ctJac (double mu, double x[]);