diff --git a/doc/manual/conversion.tex b/doc/manual/conversion.tex
index 1f23b0c0..ac3d389a 100644
--- a/doc/manual/conversion.tex
+++ b/doc/manual/conversion.tex
@@ -604,11 +604,11 @@ alternative encoding schemes elegantly, using an additional parameter
 \var{encoding}. For example:
 
 \begin{verbatim}
-t_State = enum('SEARCH', 'CONFIRM', 'SYNC', encoding="one_hot")
+t_State = enum('SEARCH', 'CONFIRM', 'SYNC', encoding='one_hot')
 \end{verbatim}
 
-The default encoding is \code{``binary''}; the other possibilities are
-\code{``one_hot''} and \code{``one_cold''}. This parameter only
+The default encoding is \code{'binary'}; the other possibilities are
+\code{'one_hot'} and \code{'one_cold'}. This parameter only
 affects the conversion output, not the behavior of the type. Verilog
 case statements are optimized for an efficient implementation
 according to the encoding. Note that in contrast, a Verilog designer
diff --git a/doc/manual/reference.tex b/doc/manual/reference.tex
index 8ce87635..292352f7 100644
--- a/doc/manual/reference.tex
+++ b/doc/manual/reference.tex
@@ -222,7 +222,7 @@ defaults to zero.  This function is especially useful in conjunction
 with the \class{intbv} class, that also works with downward indexing.
 \end{funcdesc}
 
-\begin{funcdesc}{enum}{arg \optional{, arg \moreargs} \optional{encoding=''binary''}}
+\begin{funcdesc}{enum}{arg \optional{, arg \moreargs} \optional{encoding='binary'}}
 Returns an enumeration type.
 
 The arguments should be string literals that represent the desired
@@ -233,9 +233,10 @@ t_EnumType = enum('ATTR_NAME_1', 'ATTR_NAME_2', ...)
 \end{verbatim}
 The enumeration type identifiers are available as attributes of
 the type name, for example: \code{t_EnumType.ATTR_NAME_1}
+
 The optional keyword argument \var{encoding} specifies the encoding
-scheme used in Verilog output. The available encodings are \code{``binary''},
-\code{``one_hot''}, and \code{``one_cold''}.
+scheme used in Verilog output. The available encodings are \code{'binary'},
+\code{'one_hot'}, and \code{'one_cold'}.
 \end{funcdesc}
 
 \begin{funcdesc}{instances}{}