diff --git a/spyro/solvers/elastic_wave/local_abc.py b/spyro/solvers/elastic_wave/local_abc.py
index 0991715a..fd0a7467 100644
--- a/spyro/solvers/elastic_wave/local_abc.py
+++ b/spyro/solvers/elastic_wave/local_abc.py
@@ -188,10 +188,10 @@ def stacey_terms(ndim, rho, c_p, c_s,
     sig_xx = -rho*c_p*ux_dt + rho*c_s*(c_p - 2*c_s)*uz_dz
     if ndim == 3:
         sig_xx += rho*c_s*(c_p - 2*c_s)*uy_dy
-    F_t += (sig_zx*v[iz] + sig_xx*v[ix])*ds(3, scheme=qr_s)
+    F_t += (sig_zx*v[iz] + sig_xx*v[ix])*ds(4, scheme=qr_s)
     if ndim == 3:
         sig_yx = -rho*c_s*uy_dt - rho*c_s*(c_p - 2*c_s)*ux_dy
-        F_t += sig_yx*v[iy]*ds(3, scheme=qr_s)
+        F_t += sig_yx*v[iy]*ds(4, scheme=qr_s)
 
     if ndim == 3:
         # Plane y = 0
@@ -206,4 +206,4 @@ def stacey_terms(ndim, rho, c_p, c_s,
         sig_yy = -rho*c_p*uy_dt + rho*c_s*(c_p - 2*c_s)*(uz_dz + ux_dx)
         F_t += (sig_zy*v[iz] + sig_xy*v[ix] + sig_yy*v[iy])*ds(6, scheme=qr_s)
 
-    return F_t
\ No newline at end of file
+    return F_t