diff --git a/lib/AI/Categorizer.pm b/lib/AI/Categorizer.pm
index 05281a2..3e677d9 100644
--- a/lib/AI/Categorizer.pm
+++ b/lib/AI/Categorizer.pm
@@ -162,7 +162,7 @@ AI::Categorizer - Automatic Text Categorization
    print "Assigned categories: ", join ', ', $hypothesis->categories, "\n";
    print "Best category: ", $hypothesis->best_category, "\n";
  }
- 
+
 =head1 DESCRIPTION
 
 C<AI::Categorizer> is a framework for automatic text categorization.
diff --git a/lib/AI/Categorizer/Collection.pm b/lib/AI/Categorizer/Collection.pm
index edba9c1..bb8e893 100644
--- a/lib/AI/Categorizer/Collection.pm
+++ b/lib/AI/Categorizer/Collection.pm
@@ -85,7 +85,7 @@ AI::Categorizer::Collection - Access stored documents
     ...
   }
   $c->rewind; # For further operations
-  
+
 =head1 DESCRIPTION
 
 This abstract class implements an iterator for accessing documents in
diff --git a/lib/AI/Categorizer/Collection/Files.pm b/lib/AI/Categorizer/Collection/Files.pm
index 5307223..cff5f3f 100644
--- a/lib/AI/Categorizer/Collection/Files.pm
+++ b/lib/AI/Categorizer/Collection/Files.pm
@@ -109,7 +109,7 @@ AI::Categorizer::Collection::Files - One document per file
     ...
   }
   $c->rewind; # For further operations
-  
+
 =head1 DESCRIPTION
 
 This implements a Collection class in which each document exists as a
diff --git a/lib/AI/Categorizer/FeatureSelector/DocFrequency.pm b/lib/AI/Categorizer/FeatureSelector/DocFrequency.pm
index 85315a6..f2c5dbc 100644
--- a/lib/AI/Categorizer/FeatureSelector/DocFrequency.pm
+++ b/lib/AI/Categorizer/FeatureSelector/DocFrequency.pm
@@ -69,3 +69,5 @@ the KnowledgeSet class.
 
 Creates a new KnowledgeSet and returns it.  Accepts the following
 parameters:
+
+=back
diff --git a/lib/AI/Categorizer/Learner/NaiveBayes.pm b/lib/AI/Categorizer/Learner/NaiveBayes.pm
index 22b1e3b..29d0309 100644
--- a/lib/AI/Categorizer/Learner/NaiveBayes.pm
+++ b/lib/AI/Categorizer/Learner/NaiveBayes.pm
@@ -166,9 +166,9 @@ L<http://www.cs.cmu.edu/~yiming/publications.html>
 
 "On the Optimality of the Simple Bayesian Classifier under Zero-One
 Loss" by Pedro Domingos
-L<"http://www.cs.washington.edu/homes/pedrod/mlj97.ps.gz">
+L<http://www.cs.washington.edu/homes/pedrod/mlj97.ps.gz>
 
 A simple but complete example of Bayes' Theorem from Dr. Math
-L<"http://www.mathforum.com/dr.math/problems/battisfore.03.22.99.html">
+L<http://www.mathforum.com/dr.math/problems/battisfore.03.22.99.html>
 
 =cut
diff --git a/lib/AI/Categorizer/Storable.pm b/lib/AI/Categorizer/Storable.pm
index 319d150..2dd7254 100644
--- a/lib/AI/Categorizer/Storable.pm
+++ b/lib/AI/Categorizer/Storable.pm
@@ -32,7 +32,7 @@ AI::Categorizer::Storable - Saving and Restoring State
   $object->save_state($path);
   ... time passes ...
   $object = Class->restore_state($path);
-  
+
 =head1 DESCRIPTION
 
 This class implements methods for storing the state of an object to a
@@ -55,6 +55,8 @@ be saved.
 This class method reads the file specified by C<$path> and returns the
 object that was previously stored there using C<save_state()>.
 
+=back
+
 =head1 SEE ALSO
 
 AI::Categorizer(3), Storable(3)