diff --git a/Article/notions.tex b/Article/notions.tex
index 06b6ed5cf107e2ec7b0874719690026eb9d12371..fa186bbaf1c60afcf439379ed1de1485242728cf 100755
--- a/Article/notions.tex
+++ b/Article/notions.tex
@@ -62,9 +62,9 @@ also based on digital straight lines is also used in this work.
 
 \begin{definition}
 A directional scan $DS$ is an ordered partition restricted to the image
-domain $\mathcal{I}$ of a digital straight line $\mathcal{D}$,
-called the {\it scan strip}, into scans $S_i$, each of them being a segment
-of a naive line $\mathcal{N}_i$ orthogonal to $\mathcal{D}$.
+domain $\mathcal{I}$ of a digital straight line $\mathcal{D}$, called the
+{\it scan strip}, into scans $S_i$, each of them being a segment of a naive
+line $\mathcal{N}_i$, called a {\it scan line}, orthogonal to $\mathcal{D}$.
 \end{definition}
 
 \begin{equation}