diff --git a/doc/01_quick_start.qbk b/doc/01_quick_start.qbk
index 6341e61..ae5f828 100644
--- a/doc/01_quick_start.qbk
+++ b/doc/01_quick_start.qbk
@@ -44,7 +44,7 @@ This is because we know that string value `"100"` converts to a valid value of `
       // deal with it
     }
 
-This version throws an exception upon an attempt to access a non-existent contained value. If your way of dealing with the missing value is to use some default, like `0`, there exists a yet another alternative:
+This version throws an exception upon an attempt to access a nonexistent contained value. If your way of dealing with the missing value is to use some default, like `0`, there exists a yet another alternative:
 
     int k = convert(text).value_or(0);
 
diff --git a/doc/html/boost_optional/quick_start.html b/doc/html/boost_optional/quick_start.html
index dd8491a..0388d43 100644
--- a/doc/html/boost_optional/quick_start.html
+++ b/doc/html/boost_optional/quick_start.html
@@ -100,7 +100,7 @@
 <span class="special">}</span>
 </pre>
 <p>
-        This version throws an exception upon an attempt to access a non-existent
+        This version throws an exception upon an attempt to access a nonexistent
         contained value. If your way of dealing with the missing value is to use
         some default, like <code class="computeroutput"><span class="number">0</span></code>, there exists
         a yet another alternative:
diff --git a/doc/html/boost_optional/quick_start/optional_return_values.html b/doc/html/boost_optional/quick_start/optional_return_values.html
index 9ad85ef..fef09ff 100644
--- a/doc/html/boost_optional/quick_start/optional_return_values.html
+++ b/doc/html/boost_optional/quick_start/optional_return_values.html
@@ -84,7 +84,7 @@
 <span class="special">}</span>
 </pre>
 <p>
-        This version throws an exception upon an attempt to access a non-existent
+        This version throws an exception upon an attempt to access a nonexistent
         contained value. If your way of dealing with the missing value is to use
         some default, like <code class="computeroutput"><span class="number">0</span></code>, there exists
         a yet another alternative: