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+      DOUBLE PRECISION FUNCTION sla_EPCO (K0, K, E)
+*+
+*     - - - - -
+*      E P C O
+*     - - - - -
+*
+*  Convert an epoch into the appropriate form - 'B' or 'J'
+*
+*  Given:
+*     K0    char    form of result:  'B'=Besselian, 'J'=Julian
+*     K     char    form of given epoch:  'B' or 'J'
+*     E     dp      epoch
+*
+*  Called:  sla_EPB, sla_EPJ2D, sla_EPJ, sla_EPB2D
+*
+*  Notes:
+*
+*     1) The result is always either equal to or very close to
+*        the given epoch E.  The routine is required only in
+*        applications where punctilious treatment of heterogeneous
+*        mixtures of star positions is necessary.
+*
+*     2) K0 and K are not validated.  They are interpreted as follows:
+*
+*        o  If K0 and K are the same the result is E.
+*        o  If K0 is 'B' or 'b' and K isn't, the conversion is J to B.
+*        o  In all other cases, the conversion is B to J.
+*
+*        Note that K0 and K won't match if their cases differ.
+*
+*  P.T.Wallace   Starlink   5 September 1993
+*
+*  Copyright (C) 1995 Rutherford Appleton Laboratory
+*-
+
+      IMPLICIT NONE
+
+      CHARACTER*(*) K0,K
+      DOUBLE PRECISION E
+      DOUBLE PRECISION sla_EPB,sla_EPJ2D,sla_EPJ,sla_EPB2D
+
+
+      IF (K.EQ.K0) THEN
+         sla_EPCO=E
+      ELSE IF (K0.EQ.'B'.OR.K0.EQ.'b') THEN
+         sla_EPCO=sla_EPB(sla_EPJ2D(E))
+      ELSE
+         sla_EPCO=sla_EPJ(sla_EPB2D(E))
+      END IF
+
+      END