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diff --git a/src/slalib/dcs2c.f b/src/slalib/dcs2c.f
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+      SUBROUTINE sla_DCS2C (A, B, V)
+*+
+*     - - - - - -
+*      D C S 2 C
+*     - - - - - -
+*
+*  Spherical coordinates to direction cosines (double precision)
+*
+*  Given:
+*     A,B       dp      spherical coordinates in radians
+*                        (RA,Dec), (Long,Lat) etc
+*
+*  Returned:
+*     V         dp(3)   x,y,z unit vector
+*
+*  The spherical coordinates are longitude (+ve anticlockwise
+*  looking from the +ve latitude pole) and latitude.  The
+*  Cartesian coordinates are right handed, with the x axis
+*  at zero longitude and latitude, and the z axis at the
+*  +ve latitude pole.
+*
+*  P.T.Wallace   Starlink   October 1984
+*
+*  Copyright (C) 1995 Rutherford Appleton Laboratory
+*-
+
+      IMPLICIT NONE
+
+      DOUBLE PRECISION A,B,V(3)
+
+      DOUBLE PRECISION COSB
+
+
+
+      COSB=COS(B)
+
+      V(1)=COS(A)*COSB
+      V(2)=SIN(A)*COSB
+      V(3)=SIN(B)
+
+      END