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 The exploitation of chaotic systems to generate pseudorandom sequences is
 an hot topic~\cite{915396,915385,5376454}. Such systems are fundamentally 
-chosen due to their unpredictable character and their sensibility to initial conditions.
-
-% Souvent   les   travaux  se   limitent   Ã    itÃ©rer   une  fonction   paramÃ©trÃ©e
-% \emph{chaotique}  comme la  fonction logistique~\cite{915396,915385},  ou encore
-% celle du  chat d'Arnold~\cite{5376454}\ldots Il  reste Ã  trouver  les paramÃ¨tres
-% optimaux permettant d'Ã©viter les attracteurs de telles fonctions et garantissant
-% que les sÃ©quences de nombres  produits suivent une loi de distribution uniforme.
-% Pour vÃ©rifier  la qualitÃ© des  sorties produites il  est usuel de  soumettre les
-% PRNG   (Pseudo-Random  Number   Generator)   Ã   des   tests  statistiques   tels
-% DieHARD~\cite{Marsaglia1996}, NIST~\cite{Nist10} et TestU01~\cite{LEcuyerS07}.
-% 
-% Dans son acception vulgarisÃ©e, 
-% la notion de chaos est souvent rÃ©duite Ã  celle de forte sensibilitÃ©
-% aux conditions initiales (le fameux \og \emph{effet papillon}\fg{}): 
-% une fonction continue $k$ dÃ©finie sur un espace mÃ©trique 
-% est dite \emph{fortement sensible aux conditions initiales} si pour tout
-% point $x$ et pour toute valeur positive $\epsilon$
-% il est possible de trouver un point $y$, arbitrairement proche 
-% de $x$, et un entier $t$ tels que la distance entre les 
-% $t^{\textrm{iÃ¨mes}}$ itÃ©rÃ©s de $x$ et de $y$ 
-% -- notÃ©s $k^t(x)$ et $k^t(y)$ 
-% -- est supÃ©rieure Ã  $\epsilon$. 
+chosen due to their unpredictable character and their sensitiveness to initial conditions.
+In most cases, these generators simply consist in iterating a chaotic function like 
+the logistic map~\cite{915396,915385} or the Arnold's one~\cite{5376454}\ldots
+It thus remains to find optimal parameters in such functions so that attractors are
+avoided, guaranteeing by doing so that generated numbers follow a uniform distribution.
+In order to check the quality of the produced outputs, it is usual to test the 
+PRNGs   (Pseudo-Random  Number   Generators) with statistical batteries like
+the so-called DieHARD~\cite{Marsaglia1996}, NIST~\cite{Nist10}, or TestU01~\cite{LEcuyerS07}.
+
+In its general understanding, the chaos notion is often reduced to the strong
+sensitiveness to the initial conditions (the well known ``butterfly effect''):
+a continuous function $k$ defined on a metrical space is said 
+\emph{strongly sensitive to the initial conditions} if for all point 
+$x$ and all positive value $\epsilon$, it is possible to find another 
+point $y$, as close as possible to $x$, and an integer $t$ such that the distance
+between the $t$-th iterates of $x$ and $y$, denoted by $k^t(x)$ and $k^t(y)$,
+are larger than $\epsilon$. 
 % Cependant, dans sa dÃ©finition du chaos, 
 % Devaney~\cite{Devaney} impose Ã  la fonction chaotique deux autres propriÃ©tÃ©s 
 % appelÃ©es \emph{transitivitÃ©} et \emph{rÃ©gularitÃ©},
