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diff --git a/methods.top.tex b/methods.top.tex
index c479f49..b54b50f 100644
--- a/methods.top.tex
+++ b/methods.top.tex
@@ -1,9 +1,9 @@
 \section{iTasks}
-\gls{TOP} is a recent programming paradigm implemented as
+\gls{TOP} is a modern recent programming paradigm implemented as
 \gls{iTasks}\cite{achten_introduction_2015} in the pure lazy functional
 language \gls{Clean}\cite{brus_cleanlanguage_1987}. \gls{iTasks} is a
-\gls{EDSL} to model workflow tasks in the broadest sense. A \CI{Task} is just
-a function that, given some state, returns the observable \CI{TaskValue}. The
+\gls{EDSL} to model workflow tasks in the broadest sense. A \gls{Task} is just
+a function that --- given some state --- returns the observable \CI{TaskValue}. The
 \CI{TaskValue} of a \CI{Task} can have different states. Not all state
 transitions are possible as shown in Figure~\ref{fig:taskvalue}. Once a value
 is stable it can never become unstable again. Stability is often reached
@@ -19,7 +19,7 @@ image in the \CI{NoValue} state, the second image does not have all the fields
 filled in and therefore the \CI{TaskValue} remains \CI{Unstable}. In the third
 image all fields are entered and the \CI{TaskValue} transitions to the
 \CI{Unstable} state. When the user presses \emph{Continue} the value becomes
-\CI{Stable} and can not be changed any further.
+\CI{Stable} and cannot be changed any further.
 
 \begin{figure}[H]
 	\centering
@@ -27,7 +27,7 @@ image all fields are entered and the \CI{TaskValue} transitions to the
 	\caption{The states of a \CI{TaskValue}}\label{fig:taskvalue}
 \end{figure}
 
-\begin{lstlisting}[language=Clean,label={lst:taskex},%
+\begin{lstlisting}[label={lst:taskex},%
 	caption={An example \gls{Task} for entering a name}]
 :: Name = { firstname :: String
           , lastname  :: String
@@ -42,6 +42,7 @@ enterName = enterInformation "Enter your name" []
 \end{lstlisting}
 
 \begin{figure}[H]
+	\centering
 	\begin{subfigure}{.25\textwidth}
 		\centering
 		\includegraphics[width=.9\linewidth]{taskex1}
@@ -60,24 +61,26 @@ enterName = enterInformation "Enter your name" []
 	\caption{Example of a generated user interface}
 \end{figure}
 
-For a type to be suitable it must have instances for a collection of generic
-functions that are captured in the class \CI{iTask}. Basic types have
+For a type to be suitable, it must have instances for a collection of generic
+functions that is captured in the class \CI{iTask}. Basic types have
 specialization instances for these functions and show an according interface.
 Generated interfaces can be modified with decoration operators.
 
 \section{Combinators}
+\todo{check and refine}
 \Glspl{Task} can be combined using so called \gls{Task}-combinators.
 Combinators describe relations between \glspl{Task}. \Glspl{Task} can be
 combined in parallel, sequenced and their result values can be converted to
-\glspl{SDS}. Moreover, a very important combinator is the step combinator that
-starts a new task according to the \CI{TaskValue}. The type signatures of the
-basic combinators are shown in Listing~\ref{lst:combinators}.
+\glspl{SDS}. Moreover, a very important combinator is the step combinator which
+starts a new task according to specified predicates on the \CI{TaskValue}.
+Type signatures of the basic combinators are shown in
+Listing~\ref{lst:combinators}.
 
 \begin{itemize}
 	\item Step:
 
 		The step combinator is used to start \glspl{Task} when a predicate on
-		the \CI{TaskValue} holds or an action has been taken place. The bind
+		the \CI{TaskValue} holds or an action has taken place. The bind
 		operator can be written as a step combinator.
 		\begin{lstlisting}[language=Clean]
 (>>=) infixl 1 :: (Task a) (a -> (Task b)) -> (Task b) | iTask a & iTask b
@@ -97,7 +100,7 @@ basic combinators are shown in Listing~\ref{lst:combinators}.
 		dictates.
 \end{itemize}
 
-\begin{lstlisting}[language=Clean,%
+\begin{lstlisting}[%
 	caption={\Gls{Task}-combinators},label={lst:combinators}]
 //Step combinator
 (>>*)  infixl 1 :: (Task a) [TaskCont a (Task b)] -> Task b     | iTask a & iTask b
@@ -116,24 +119,38 @@ basic combinators are shown in Listing~\ref{lst:combinators}.
 (-&&-) infixr 4 :: (Task a) (Task b)              -> Task (a,b) | iTask a & iTask b
 \end{lstlisting}
 
-\section{\acrlongpl{SDS}}
+\section{Shared Data Sources}
 \Glspl{SDS} are an abstraction over resources that are available in the world
 or in the \gls{iTasks} system. The shared data can be a file on disk, it can be
 the time, a random integer or just some data stored in memory. The actual
 \gls{SDS} is just a record containing functions on how to read and write the
-source. In these functions the \CI{*World} is available and therefore it can
-interact with the outside world. The \CI{*IWorld} is also available and
-therefore the functions can also access other shares, possibly combining them.
+source. In these functions the \CI{*IWorld} which in turn contains the real
+program \CI{*World}. Accessing the outside world is required for interacting
+with it and thus the functions can access files on disk, raw memory, other
+shares and combine shares.
 
 The basic operations for \glspl{SDS} are get, set and update. The signatures
-for these functions are shown in Listing~\ref{lst:shares}. All of the
-operations are atomic in the sense that during reading no other tasks are
-executed.
+for these functions are shown in Listing~\ref{lst:shares}. By default, all
+shares are files containing a \gls{JSON} encoded version of the object and thus
+are persistent between restarts of the program. Library functions for shares
+residing in memory are available as well. The three main operations on shares
+are atomic in the sense that during reading no other tasks are executed.
+
+The basic type for \glspl{SDS} has three \todo{parametric
+lenses}\cite{domoszlai_parametric_2014}.
 
 \begin{lstlisting}[%
-	language=Clean,label={lst:shares},caption={\Gls{SDS} functions}]
+	label={lst:shares},caption={\Gls{SDS} functions}]
+:: RWShared p r w = ... 
+:: ReadWriteShared r w :== RWShared () r w
+:: ROShared p r :== RWShared p () r
+:: ReadOnlyShared r :== ROShared () r
+
+:: Shared r :== ReadWriteShared r r
+
 get ::          (ReadWriteShared r w)           -> Task r | iTask r
 set :: w        (ReadWriteShared r w)           -> Task w | iTask w
 upd :: (r -> w) (ReadWriteShared r w)           -> Task w | iTask r & iTask w
 
+sharedStore :: String a -> Shared a | JSONEncode{|*|}, JSONDecode{|*|}
 \end{lstlisting}