diff --git a/lib/rgl/adjacency.rb b/lib/rgl/adjacency.rb
index 5d7a0ff..80691b7 100644
--- a/lib/rgl/adjacency.rb
+++ b/lib/rgl/adjacency.rb
@@ -161,6 +161,7 @@ def basic_add_edge(u, v)
 
   end # class AdjacencyGraph
 
+
   module Graph
 
     # Convert a general graph to an AdjacencyGraph. If the graph is directed,
diff --git a/lib/rgl/bellman_ford.rb b/lib/rgl/bellman_ford.rb
index 6effc76..9fb53db 100644
--- a/lib/rgl/bellman_ford.rb
+++ b/lib/rgl/bellman_ford.rb
@@ -27,6 +27,7 @@ def initialize(graph)
 
   end
 
+  # This class implements {Graph#bellman_ford_shortest_paths}.
   class BellmanFordAlgorithm
 
     # Initializes Bellman-Ford algorithm for a _graph_ with provided edges weights map.
@@ -89,6 +90,7 @@ def relax_edge(u, v)
 
   end # class BellmanFordAlgorithm
 
+
   module Graph
 
     # Finds the shortest paths from the _source_ to each vertex of the graph.
diff --git a/lib/rgl/bipartite.rb b/lib/rgl/bipartite.rb
index c6fd209..f5565d3 100644
--- a/lib/rgl/bipartite.rb
+++ b/lib/rgl/bipartite.rb
@@ -41,6 +41,7 @@ def bipartite?
 
   end # module Graph
 
+
   class BipartiteBFSIterator < BFSIterator
 
     attr_reader :bipartite_sets_map, :found_odd_cycle
diff --git a/lib/rgl/dijkstra.rb b/lib/rgl/dijkstra.rb
index 3cfad14..bcc3b09 100644
--- a/lib/rgl/dijkstra.rb
+++ b/lib/rgl/dijkstra.rb
@@ -6,6 +6,7 @@
 
 module RGL
 
+  # This class implements {Graph#dijkstra_shortest_path} and {Graph#dijkstra_shortest_paths}
   class DijkstraAlgorithm
 
     # Distance combinator is a lambda that accepts the distance (usually from the source) to vertex _u_ and the weight
@@ -103,6 +104,7 @@ def build_edge_weights_map(edge_weights_map)
 
   end # class DijkstraAlgorithm
 
+
   module Graph
 
     # Finds the shortest path from the _source_ to the _target_ in the graph.
diff --git a/lib/rgl/edge_properties_map.rb b/lib/rgl/edge_properties_map.rb
index 6db3738..87cc2f5 100644
--- a/lib/rgl/edge_properties_map.rb
+++ b/lib/rgl/edge_properties_map.rb
@@ -37,6 +37,7 @@ def report_missing_property(property, u, v)
 
   end # EdgePropertiesMap
 
+
   class NonNegativeEdgePropertiesMap < EdgePropertiesMap
 
     private
@@ -52,4 +53,4 @@ def report_negative_property(property, u, v)
 
   end
 
-end
\ No newline at end of file
+end
diff --git a/lib/rgl/edmonds_karp.rb b/lib/rgl/edmonds_karp.rb
index 4953ad8..f0c3fc1 100644
--- a/lib/rgl/edmonds_karp.rb
+++ b/lib/rgl/edmonds_karp.rb
@@ -116,6 +116,7 @@ def handle_tree_edge(u, v)
 
   end # class EdmondsKarpAlgorithm
 
+
   module Graph
 
     # Finds the maximum flow from the _source_ to the _sink_ in the graph.
diff --git a/lib/rgl/implicit.rb b/lib/rgl/implicit.rb
index aa71da2..85ad563 100644
--- a/lib/rgl/implicit.rb
+++ b/lib/rgl/implicit.rb
@@ -97,6 +97,7 @@ def edge_iterator(&block)
 
   end # class ImplicitGraph
 
+
   module Graph
 
     # Returns a new {ImplicitGraph} which has as vertices all vertices of the
diff --git a/lib/rgl/prim.rb b/lib/rgl/prim.rb
index b647f78..4cdd8a3 100644
--- a/lib/rgl/prim.rb
+++ b/lib/rgl/prim.rb
@@ -34,6 +34,7 @@ def minimum_spanning_tree(start_vertex = nil)
 
   end # class PrimAlgorithm
 
+
   module Graph
 
     # Finds the minimum spanning tree of the graph.
diff --git a/lib/rgl/topsort.rb b/lib/rgl/topsort.rb
index 98f5987..6b86276 100644
--- a/lib/rgl/topsort.rb
+++ b/lib/rgl/topsort.rb
@@ -8,10 +8,10 @@ module RGL
   #
   # The topological sort algorithm creates a linear ordering of the vertices
   # such that if edge (u,v) appears in the graph, then u comes before v in
-  # the ordering. The graph must be a directed acyclic graph (DAG).
+  # the ordering. The graph must be a directed acyclic graph.
   #
   # The iterator can also be applied to an undirected graph or to a directed graph
-  # which contains a cycle. In this case, the Iterator does not reach all
+  # which contains a cycle. In this case, the iterator does not reach all
   # vertices. The implementation of {Graph#acyclic?} uses this fact.
   #
   # @see Graph#topsort_iterator
@@ -60,6 +60,7 @@ def at_end?
 
   end # class TopsortIterator
 
+
   module Graph
 
     # @return [TopsortIterator] for the graph.
diff --git a/lib/rgl/traversal.rb b/lib/rgl/traversal.rb
index ce374e0..7d150e6 100644
--- a/lib/rgl/traversal.rb
+++ b/lib/rgl/traversal.rb
@@ -104,6 +104,7 @@ def next_vertex
 
   end # class BFSIterator
 
+
   module Graph
 
     # @return [BFSIterator] starting at vertex _v_.
@@ -161,6 +162,7 @@ class DFSVisitor
 
   end # class DFSVisitor
 
+
   module Graph
 
     # @return [DFSIterator] staring at vertex _v_.