fix reflection coefficient description

README.md

@@ -50,7 +50,7 @@ Room Impulse Responses (RIRs) simulation using the Image Source Method (ISM). Fo
 * **room_sz** : *array_like with 3 elements.*
         Size of the room (in meters).
 * **beta** : *array_like with 6 elements.*
-        Reflection coefficients of the walls as $[beta_{x0}, beta_{x1}, beta_{y0}, beta_{y1}, beta_{z0}, beta_{z1}]$, where $beta_{x0}$ is the coeffcient of the wall parallel to the x axis closest to the origin of coordinates system and $beta_{x1}$ the farthest.
+        Reflection coefficients of the walls as $[beta_{x0}, beta_{x1}, beta_{y0}, beta_{y1}, beta_{z0}, beta_{z1}]$, where $beta_{x0}$ and $beta_{x1}$ are the reflection coefficents of the walls orthogonal to the x axis at x=0 and x=room_sz[0], respectively.
 * **pos_src**, **pos_rcv** : *ndarray with 2 dimensions and 3 columns.*
         Position of the sources and the receivers (in meters).
 * **nb_img** : *array_like with 3 integer elements*
@@ -137,7 +137,7 @@ Estimation of the reflection coefficients needed to have the desired reverberati
 #### Returns
 
 *ndarray with 6 elements.*
-        Reflection coefficients of the walls as $[beta_{x0}, beta_{x1}, beta_{y0}, beta_{y1}, beta_{z0}, beta_{z1}]$, where $beta_{x0}$ is the coeffcient of the wall parallel to the x axis closest to the origin of coordinates system and $beta_{x1}$ the farthest.
+        Reflection coefficients of the walls as $[beta_{x0}, beta_{x1}, beta_{y0}, beta_{y1}, beta_{z0}, beta_{z1}]$, where $beta_{x0}$ and $beta_{x1}$ are the reflection coefficents of the walls orthogonal to the x axis at x=0 and x=room_sz[0], respectively.
 
 ### `att2t_SabineEstimator`