diff --git a/fvn_test/Makefile b/fvn_test/Makefile
index 97ea79d..381b4f7 100644
--- a/fvn_test/Makefile
+++ b/fvn_test/Makefile
@@ -6,7 +6,8 @@ test_det$(exext) test_matcon$(exext) test_matev$(exext) test_inter1d$(exext) \
 test_inter2d$(exext) test_inter3d$(exext) test_akima$(exext) test_lsp$(exext) test_muller$(exext) \
 test_integ$(exext) test_bsyn$(exext) test_bsjn$(exext) test_bskn$(exext) test_bsin$(exext) test_operators$(exext) test_ze1$(exext) \
 test_besri$(exext) test_besrj$(exext) test_bestime$(exext) \
-test_sparse_zi$(exext) test_sparse_zl$(exext) test_sparse_di$(exext) test_sparse_dl$(exext)
+test_sparse_zi$(exext) test_sparse_zl$(exext) test_sparse_di$(exext) test_sparse_dl$(exext) \
+test_lm$(exext)
 
 prog:$(programs)
 
@@ -21,3 +22,8 @@ clean:
 		$(F95) $(F95FLAGS) -c $< -o $@
 
 $(programs): init_random_seed.o
+
+test_lm.o: test_lm.f90 excursion.o
+
+test_lm$(exext): test_lm.o excursion.o
+		$(LINK) $(LINKFLAGS) test_lm.o excursion.o $(LINKFVN) -o $@
diff --git a/fvn_test/excursion.f90 b/fvn_test/excursion.f90
new file mode 100644
index 0000000..db38fa6
--- /dev/null
+++ b/fvn_test/excursion.f90
@@ -0,0 +1,6 @@
+module excursion
+
+real(8), dimension(:), pointer :: xm => NULL()
+real(8), dimension(:), pointer :: ym => NULL()
+
+end module
diff --git a/fvn_test/test_lm.f90 b/fvn_test/test_lm.f90
new file mode 100644
index 0000000..74e54f9
--- /dev/null
+++ b/fvn_test/test_lm.f90
@@ -0,0 +1,78 @@
+program gls
+use fvn_misc
+use excursion
+implicit none
+
+    interface
+        subroutine zef(m, n, x, fvec, iflag)
+            integer(4), intent(in) :: m,n
+            real(8), dimension(:), intent(in) :: x
+            real(8), dimension(:), intent(inout) :: fvec
+            integer(4), intent(inout) :: iflag
+        end subroutine
+    end interface
+
+
+ integer,parameter :: npoints=13,deg=3
+ integer :: status,i
+ real(kind=dp_kind) :: xstep,xc,yc
+ real(kind=dp_kind) :: coeff(deg+1)
+ real(kind=dp_kind) :: fvec(npoints)
+ integer(4) :: iwa(deg+1)
+ integer(4) :: info
+ real(8) :: tol
+ 
+ allocate(xm(npoints),ym(npoints))
+ 
+ xm = (/ -3.8,-2.7,-2.2,-1.9,-1.1,-0.7,0.5,1.7,2.,2.8,3.2,3.8,4. /)
+ ym = (/ -3.1,-2.,-0.9,0.8,1.8,0.4,2.1,1.8,3.2,2.8,3.9,5.2,7.5 /)
+ open(2,file='fvn_lsp_double_mesure.dat')
+ open(3,file='fvn_lm.dat')
+ do i=1,npoints
+    write(2,44) xm(i),ym(i)
+ end do
+ close(2)
+ 
+ coeff=1.
+ call fvn_lm(zef,npoints,deg+1,coeff,info)
+ write(*,*) "info : ",info
+ 
+ xstep=(xm(npoints)-xm(1))/1000.
+ do i=1,1000
+    xc=xm(1)+(i-1)*xstep
+    yc=poly(xc,coeff)
+    write(3,44) xc,yc
+ end do
+ close(3)
+write(*,*) "All done, plot results with gnuplot using command :"
+write(*,*) "pl 'fvn_lsp_double_mesure.dat' u 1:2 w p,'fvn_lm.dat' u 1:2 w l"
+44      FORMAT(4(1X,1PE22.14))
+contains
+function poly(x,coeff)
+    use fvn_common
+    implicit none
+    real(kind=dp_kind) :: x
+    real(kind=dp_kind) :: coeff(deg+1)
+    real(kind=dp_kind) :: poly
+    integer :: i
+    poly=0.
+    do i=1,deg+1
+         poly=poly+coeff(i)*x**(i-1)
+    end do
+end function
+end program
+
+subroutine zef(m, n, x, fvec, iflag)
+    use excursion
+    implicit none
+    integer(4), intent(in) :: m,n
+    real(8), dimension(:), intent(in) :: x
+    real(8), dimension(:), intent(inout) :: fvec
+    integer(4), intent(inout) :: iflag
+    
+    integer(4) :: i
+        
+    do i=1,m
+        fvec(i)=ym(i)-(x(1)+x(2)*xm(i)+x(3)*xm(i)**2+x(4)*xm(i)**3)
+    enddo
+end subroutine
\ No newline at end of file