diff --git a/src/backend/sgpemv2/global_preferences.hh b/src/backend/sgpemv2/global_preferences.hh
index f023465..2e99fbc 100644
--- a/src/backend/sgpemv2/global_preferences.hh
+++ b/src/backend/sgpemv2/global_preferences.hh
@@ -155,7 +155,6 @@ namespace sgpem
         -# Via command line arguments
         -# By a backend::Plugin::on_init() method called when loading an external DSO. This is perfectly normal and permitted.
      */
-
     int _speed;
   };
 }
diff --git a/src/backend/sgpemv2/resource.hh b/src/backend/sgpemv2/resource.hh
index f803a63..cd80aa8 100644
--- a/src/backend/sgpemv2/resource.hh
+++ b/src/backend/sgpemv2/resource.hh
@@ -29,16 +29,31 @@ namespace sgpem
   class Resource;
   class SerializeVisitor;
 
+  /** \brief An abstract class representing a resource 
+   *
+   * A resource in a real operating system could be a printer,
+   * a socket, a chunk of memory, or a simple file.
+   */
   class SG_DLLEXPORT Resource
   {
   public:
     virtual ~Resource();
 
+    /** \brief See if two different states point to the same resource */
     virtual bool operator==(const Resource& op2) const = 0;
 
+    /** \brief Returns the resource name */
     virtual Glib::ustring get_name() const = 0;
+
+    /** \brief Return the number of places this resource has available
+     * before becoming unavailable
+     *
+     * E.g. if a resource has two places, it can fulfill only two
+     * ::SubRequests at each instant 
+     */
     virtual unsigned int get_places() const = 0;
 
+    /** \brief Used to serialize the informations of this entity */
     virtual void serialize(SerializeVisitor& translator) const = 0;
   };