diff --git a/src/inverse_problem_for_source/README_howto_perform_source_inversions_for_a_constant_model_with_SPECFEM.txt b/src/inverse_problem_for_source/README_howto_perform_source_inversions_for_a_constant_model_with_SPECFEM.txt
index b87964381..51eb4d5d4 100644
--- a/src/inverse_problem_for_source/README_howto_perform_source_inversions_for_a_constant_model_with_SPECFEM.txt
+++ b/src/inverse_problem_for_source/README_howto_perform_source_inversions_for_a_constant_model_with_SPECFEM.txt
@@ -1,17 +1,17 @@
 
-Here is what SPECFEM3D users classically do to relocate earthquake sources (paragraph taken from a 
+Here is what SPECFEM3D users classically do to relocate earthquake sources (paragraph taken from a
 text written by Federica Magnoni and Emanuele Casarotti for Italy, with minor changes by Dimitri Komatitsch):
 
-"As initial source parameters of the chosen events we use Time Domain Moment Tensor solutions 
-(TDMT, Dreger and Helmberger, 1993; Scognamiglio et al. 2009) that are calculated by inverting full 
-three-component traces of regional broad-band stations using 1D wave speed models. Before starting 
+"As initial source parameters of the chosen events we use Time Domain Moment Tensor solutions
+(TDMT, Dreger and Helmberger, 1993; Scognamiglio et al. 2009) that are calculated by inverting full
+three-component traces of regional broad-band stations using 1D wave speed models. Before starting
 the tomographic inversion, we then exploit the initial 3D model of the structure under study
-to recalculate the source parameters of the considered events. The TDMT solutions, based on 
-1D wave speed models, are considered as initial solutions and we invert for the six moment tensor 
-components and the event location by using the technique presented in Liu et al. (2004). We use 
-SPECFEM3D to numerically calculate the Frechet derivatives with respect to the source parameters 
-based on 3D models and we minimize a waveform misfit function to invert for source solutions. If 
-the variance reduction of the solution with the 3D model is significant, this is considered as the 
+to recalculate the source parameters of the considered events. The TDMT solutions, based on
+1D wave speed models, are considered as initial solutions and we invert for the six moment tensor
+components and the event location by using the technique presented in Liu et al. (2004). We use
+SPECFEM3D to numerically calculate the Frechet derivatives with respect to the source parameters
+based on 3D models and we minimize a waveform misfit function to invert for source solutions. If
+the variance reduction of the solution with the 3D model is significant, this is considered as the
 new moment tensor solution of the event."
 
 This is performed using one of the two following packages, depending on the language you prefer to use:
@@ -19,7 +19,7 @@ CMT3D (written by Qinya Liu et al. in Fortran), or pyCMT3D (same package, but tr
 The two packages are included in this directory.
 
 This source inversion technique comes from the following paper by Qinya Liu et al.:
-http://komatitsch.free.fr/preprints/bssa_Qinya_inversion_2004.pdf 
+http://komatitsch.free.fr/preprints/bssa_Qinya_inversion_2004.pdf
 and in which the Frechet derivatives are computed using finite-differences.
 Here is the full reference of the paper: