--- /dev/null
+C-----------------------------------------------------------------------
+#include "pdf/pilot.h"
+ SUBROUTINE SFCTQ49(DX,DSCAL,
+ + DUPV,DDNV,DSEA,DSEAD,DSTR,DCHM,DBOT,DTOP,DGL)
+C
+C ********************************************************************
+C * *
+C * Interface to CTEQset of structure functions *
+C * *
+C * Author: H. Plothow-Besch (CERN-PPE) *
+C * *
+C ********************************************************************
+C
+C :::::::::::: Structure functions from the CTEQ collaboration version 4
+C :::::::::::: Lambda = 0.174 GeV (MS_bar) low Q**2
+C
+#include "pdf/impdp.inc"
+ PARAMETER (ISET=10)
+#include "pdf/w50511.inc"
+C
+ X = DX
+ Q = DSCAL
+C
+C generate the individual structure fcn calls
+C
+ UPV = Ctq4Fn(ISET, 1,X,Q)
+ DNV = Ctq4Fn(ISET, 2,X,Q)
+ SEAU = Ctq4Fn(ISET,-1,X,Q)
+ DSEA = SEAU*X
+ DUPV = (UPV-SEAU)*X
+ SEAD = Ctq4Fn(ISET,-2,X,Q)
+ DSEAD = SEAD*X
+ DDNV = (DNV-SEAD)*X
+ STR = Ctq4Fn(ISET,-3,X,Q)
+ DSTR = STR*X
+ CHM = Ctq4Fn(ISET,-4,X,Q)
+ DCHM = CHM*X
+ BOT = Ctq4Fn(ISET,-5,X,Q)
+ DBOT = BOT*X
+ TOP = 0.
+C IF (DSCAL.GT.TMAS) TOP = Ctq4Fn(ISET,-6,X,Q)
+ DTOP = TOP*X
+ GL = Ctq4Fn(ISET, 0,X,Q)
+ DGL = GL*X
+C
+ RETURN
+ END