diff --git a/README.md b/README.md
index 0222a96..0086051 100644
--- a/README.md
+++ b/README.md
@@ -4,7 +4,7 @@ The 2.5D modeling technique produces a 3D wavefield using a 2D geological model,
 The program can handle various modeling scenarios including viscoacoustic, isotropic viscoelastic, anisotropic viscoelastic (VTI, ORT, and TTI), solid and water free surfaces, and water-solid interfaces.
 
 # Installment
-* SCSM2.5d OpenMP version: Compile MainOMP.f90, C_DF.f90, Gauss_Quad.f90, Grid_Model.f90, interp.f90, MATRIX_YYXZ.f90, MS_DF.f90, Viscoelastic.f90, and Viscoelastic2.f90. 
+* SCSM2.5d OpenMP version: Compile __MainOMP.f90, C_DF.f90, Gauss_Quad.f90, Grid_Model.f90, interp.f90, MATRIX_YYXZ.f90, MS_DF.f90, Viscoelastic.f90, and Viscoelastic2.f90__. 
 * SCSM2.5d MPI/OpenMP version: Compile MainMPIOMP.f90, C_DF.f90, Gauss_Quad.f90, Grid_Model.f90, interp.f90, MATRIX_YYXZ.f90, MS_DF.f90, Viscoelastic.f90, and Viscoelastic2.f90.
 
 By substituting MainOMP.f90 with MainMPIOMP.f90, the program can be converted to an MPI/OpenMP version that supports fully-parallel computation, utilizing cores equal to the number of wavenumber samples.