diff --git a/includes/FeedsImporter.inc b/includes/FeedsImporter.inc
index 5286b1d..cad7695 100644
--- a/includes/FeedsImporter.inc
+++ b/includes/FeedsImporter.inc
@@ -150,7 +150,7 @@ class FeedsImporter extends FeedsConfigurable {
   /**
    * Copy a FeedsImporter configuration into this importer.
    *
-   * @param FeedsImporter $importer
+   * @param FeedsConfigurable $configurable
    *   The feeds importer object to copy from.
    */
    public function copy(FeedsConfigurable $configurable) {
diff --git a/libraries/ParserCSV.inc b/libraries/ParserCSV.inc
index 6e33071..5b218bb 100644
--- a/libraries/ParserCSV.inc
+++ b/libraries/ParserCSV.inc
@@ -171,7 +171,7 @@ class ParserCSV {
   /**
    * Get the byte number where the parser left off after last parse() call.
    *
-   * @return
+   * @return int
    *  0 if all lines or no line has been parsed, the byte position of where a
    *  timeout or the line limit has been reached otherwise. This position can be
    *  used to set the start byte for the next iteration after parse() has
@@ -198,11 +198,8 @@ class ParserCSV {
    *
    * @param Iterator $lineIterator
    *   An Iterator object that yields line strings, e.g. ParserCSVIterator.
-   * @param $start
-   *   The byte number from where to start parsing the file.
-   * @param $lines
-   *   The number of lines to parse, 0 for all lines.
-   * @return
+   *
+   * @return array
    *   Two dimensional array that contains the data in the CSV file.
    */
   public function parse(Iterator $lineIterator) {
diff --git a/libraries/common_syndication_parser.inc b/libraries/common_syndication_parser.inc
index a4d373e..47b7850 100644
--- a/libraries/common_syndication_parser.inc
+++ b/libraries/common_syndication_parser.inc
@@ -13,10 +13,11 @@
 /**
  * Parse the feed into a data structure.
  *
- * @param $feed
- *  The feed object (contains the URL or the parsed XML structure.
- * @return
- *  stdClass The structured datas extracted from the feed.
+ * @param string $string
+ *   The feed object (contains the URL or the parsed XML structure).
+ *
+ * @return array|false
+ *   The structured datas extracted from the feed or FALSE in case of failures.
  */
 function common_syndication_parser_parse($string) {
   // SimpleXML can only deal with XML declaration at the start of the document,
@@ -45,10 +46,11 @@ function common_syndication_parser_parse($string) {
 /**
  * Determine the feed format of a SimpleXML parsed object structure.
  *
- * @param $xml
- *  SimpleXML-preprocessed feed.
- * @return
- *  The feed format short description or FALSE if not compatible.
+ * @param SimpleXMLElement $xml
+ *   SimpleXML-preprocessed feed.
+ *
+ * @return string|false
+ *   The feed format short description or FALSE if not compatible.
  */
 function _parser_common_syndication_feed_format_detect($xml) {
   if (!is_object($xml)) {
@@ -490,10 +492,11 @@ function _parser_common_syndication_RSS20_parse($feed_XML) {
 /**
  * Parse a date comes from a feed.
  *
- * @param $date_string
- *  The date string in various formats.
- * @return
- *  The timestamp of the string or the current time if can't be parsed
+ * @param string $date_str
+ *   The date string in various formats.
+ *
+ * @return int
+ *   The timestamp of the string or the current time if can't be parsed.
  */
 function _parser_common_syndication_parse_date($date_str) {
   // PHP < 5.3 doesn't like the GMT- notation for parsing timezones.
@@ -526,9 +529,10 @@ function _parser_common_syndication_parse_date($date_str) {
  * See http://www.w3.org/TR/NOTE-datetime for more information.
  * Originally from MagpieRSS (http://magpierss.sourceforge.net/).
  *
- * @param $date_str
- *   A string with a potentially W3C DTF date.
- * @return
+ * @param string $date_str
+ *   A potentially W3C DTF date.
+ *
+ * @return int|false
  *   A timestamp if parsed successfully or FALSE if not.
  */
 function _parser_common_syndication_parse_w3cdtf($date_str) {
@@ -563,8 +567,11 @@ function _parser_common_syndication_parse_w3cdtf($date_str) {
  * Extract the link that points to the original content (back to site or
  * original article)
  *
- * @param $links
- *  Array of SimpleXML objects
+ * @param array $links
+ *   Array of SimpleXML objects
+ *
+ * @return string
+ *   An URL if found. An empty string otherwise.
  */
 function _parser_common_syndication_link($links) {
   $to_link = '';
diff --git a/libraries/opml_parser.inc b/libraries/opml_parser.inc
index d1faefc..c5b7cb3 100644
--- a/libraries/opml_parser.inc
+++ b/libraries/opml_parser.inc
@@ -10,7 +10,8 @@
  *
  * @param $raw
  *   File contents.
- * @return
+ *
+ * @return array
  *   An array of the parsed OPML file.
  */
 function opml_parser_parse($raw) {
diff --git a/plugins/FeedsCSVParser.inc b/plugins/FeedsCSVParser.inc
index 82121b4..073a56d 100644
--- a/plugins/FeedsCSVParser.inc
+++ b/plugins/FeedsCSVParser.inc
@@ -56,12 +56,14 @@ class FeedsCSVParser extends FeedsParser {
   /**
    * Get first line and use it for column names, convert them to lower case.
    * Be aware that the $parser and iterator objects can be modified in this
-   * function since they are passed in by reference
+   * function since they are passed in by reference.
    *
    * @param ParserCSV $parser
    * @param ParserCSVIterator $iterator
-   * @return
-   *   An array of lower-cased column names to use as keys for the parsed items.
+   *
+   * @return array|false
+   *   An array of lower-cased column names to use as keys for the parsed items
+   *   or FALSE if the document was empty.
    */
   protected function parseHeader(ParserCSV $parser, ParserCSVIterator $iterator) {
     $parser->setLineLimit(1);
@@ -81,8 +83,13 @@ class FeedsCSVParser extends FeedsParser {
    *
    * @param ParserCSV $parser
    * @param ParserCSVIterator $iterator
-   * @return
-   *   An array of rows of the CSV keyed by the column names previously set
+   * @param int $start
+   *   The byte number from where to start parsing the file.
+   * @param int $limit
+   *   The number of lines to parse, 0 for all lines.
+   *
+   * @return array
+   *   An array of rows of the CSV keyed by the column names previously set.
    */
   protected function parseItems(ParserCSV $parser, ParserCSVIterator $iterator, $start = 0, $limit = 0) {
     $parser->setLineLimit($limit);
