diff --git a/NOTES.md b/NOTES.md
index 7aa1297..6041f6c 100644
--- a/NOTES.md
+++ b/NOTES.md
@@ -67,7 +67,7 @@ The first **word** specifies a command to be executed, with the rest of the
 
 The return status (see _Exit Status_) of a simple command is its exit status as
 provided by the POSIX 1003.1 waitpid function, or 128+n if the command was
-terminated by signal n. 
+terminated by signal n.
 
 #### Pipelines
 
@@ -76,7 +76,7 @@ cf. 3.2.3 Pipelines
 A pipeline is a sequence of one or more commands separated by the control operator '|'.
 
 The output of each command in the pipeline is connected via a pipe to the input
-of the next command. 
+of the next command.
 That is, each command reads the previous command’s output.
 This connection is performed before any redirections specified by the first
 command.
@@ -106,7 +106,7 @@ A list is a sequence of one or more pipelines separated by one of the
 **operators** ‘&&’, or ‘||’, and optionally terminated by a newline.
 
 AND and OR lists are sequences of one or more pipelines separated by the control
-operators ‘&&’ and ‘||’, respectively. 
+operators ‘&&’ and ‘||’, respectively.
 AND and OR lists are executed with left associativity.
 
 e.g.
@@ -144,7 +144,7 @@ executed in the list.
 
 cf. 3.2.5 Compound Commands
 
-Each group begins with the **control operator** '(' and ends with the 
+Each group begins with the **control operator** '(' and ends with the
 **control operator** ')'.
 
 Any redirections associated with a _group of commands_ apply to all commands
@@ -183,7 +183,7 @@ order:
    * command substitution (left to right)
    * word splitting
    * filename expansion
-   
+
 We only have to implement the following kinds:
    * parameter expansion
    * word splitting
@@ -253,7 +253,7 @@ cf. 3.5.8.1 Pattern Matching
 
 Any character that appears in a pattern, other than the special pattern
 characters described below, matches itself.  The NUL character may not occur in
-a pattern. 
+a pattern.
 
 The special pattern characters have the following meanings:
 '\*'
@@ -281,11 +281,11 @@ expansions are removed.
 
 cf. 3.7.3 Command Execution Environment
 
-The shell has an execution environment, which consists of the following: 
+The shell has an execution environment, which consists of the following:
 
 open files inherited by the shell at invocation, as modified by redirections
 
-the current working directory as set by cd or inherited by the shell at invocation 
+the current working directory as set by cd or inherited by the shell at invocation
 
 shell variables, passed in the environment
 
@@ -310,8 +310,8 @@ delimiter is the result of quote removal on word, and the lines in the
 here-document are not expanded. If word is unquoted, all lines of the
 here-document are subjected to parameter expansion, command substitution, and
 arithmetic expansion, the character sequence \newline is ignored, and ‘\’ must
-be used to quote the characters ‘\’, ‘$’, and ‘`’. 
-   
+be used to quote the characters ‘\’, ‘$’, and ‘`’.
+
 ## Definitions
 cf. [Bash Reference Manual](https://www.gnu.org/savannah-checkouts/gnu/bash/manual/bash.html#Definitions)
 cf. 2 Definitions
@@ -322,16 +322,16 @@ word or an operator
 
 **word**
 A sequence of characters treated as a unit by the shell. Words may not include
-unquoted metacharacters. 
+unquoted metacharacters.
 
 **operator**
 A **control operator** or a **redirection operator**.
 Operators contain at least one unquoted **metacharacter**.
 
 **control operator**
-A token that performs a control function. 
+A token that performs a control function.
 
-It is a newline or one of the following: '|', ‘||’, ‘&&’, ‘(’, or ‘)’. 
+It is a newline or one of the following: '|', ‘||’, ‘&&’, ‘(’, or ‘)’.
 
 **redirection operator**
 For our project: