diff --git a/.travis.yml b/.travis.yml
index 3ccb1ac6..a980b543 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -9,3 +9,4 @@ script:
   # the "yast-travis-ruby" script is included in the base yastdevel/ruby image
   # see https://github.com/yast/docker-yast-ruby/blob/master/yast-travis-ruby
   - docker run -it -e TRAVIS=1 -e TRAVIS_JOB_ID="$TRAVIS_JOB_ID" yast-ntp-client-image yast-travis-ruby
+  - docker run -it -e TRAVIS=1 -e TRAVIS_JOB_ID="$TRAVIS_JOB_ID" yast-ntp-client-image rake check:doc
diff --git a/src/clients/ntp-client_auto.rb b/src/clients/ntp-client_auto.rb
index 6509c1f1..d1a76ee7 100644
--- a/src/clients/ntp-client_auto.rb
+++ b/src/clients/ntp-client_auto.rb
@@ -11,12 +11,6 @@
 # goes through the configuration and return the setting.
 # Does not do any changes to the configuration.
 
-# @param function to execute
-# @param map/list of ntp-client settings
-# @return [Hash] edited settings, Summary or boolean on success depending on called function
-# @example map mm = $[ "FAIL_DELAY" : "77" ];
-# @example map ret = WFM::CallFunction ("ntp-client_auto", [ "Summary", mm ]);
-
 require "fileutils"
 
 module Yast
diff --git a/src/lib/y2ntp_client/dialog/pool.rb b/src/lib/y2ntp_client/dialog/pool.rb
index 8baf7bba..d2f2ecc4 100644
--- a/src/lib/y2ntp_client/dialog/pool.rb
+++ b/src/lib/y2ntp_client/dialog/pool.rb
@@ -11,7 +11,10 @@ module Y2NtpClient
   module Dialog
     # Dialog to add/edit ntp pool server
     class Pool < CWM::Dialog
-      # @param pool_entry [nil, Hash]
+      # @param address [String] initial address for pool to show
+      # @param options [Hash] pool options in format where
+      #   key is option and value is string for key value options
+      #   or nil for keyword options
       def initialize(address = "", options = {})
         textdomain "ntp-client"
         @address = address
@@ -53,6 +56,9 @@ def abort_button
         ""
       end
 
+      # Returns value set in dialog.
+      # @return [Array<String, Hash>] returns pair, where first one is address and second
+      #   is modified options ( see #initialize options parameter ).
       def resulting_pool
         [@address_widget.address, @options]
       end
diff --git a/src/modules/NtpClient.rb b/src/modules/NtpClient.rb
index 90c0c393..9917a9dd 100644
--- a/src/modules/NtpClient.rb
+++ b/src/modules/NtpClient.rb
@@ -353,7 +353,7 @@ def reachable_ntp_server?(server)
 
     # Test NTP server answer for a given IP version.
     # @param [String] server string host name or IP address of the NTP server
-    # @param [Fixnum] integer ip version to use (4 or 6)
+    # @param [Integer] ip_version ip version to use (4 or 6)
     # @return [Boolean] true if stderr does not include lookup error and exit
     # code is 0
     def ntp_test(server, ip_version = 4)
@@ -710,8 +710,8 @@ def read_known_servers
     #   country_server_label("Nürnberg", "")            # => " (Nürnberg)"
     #   country_server_label("", "Deutschland")         # => " (Deutschland)"
     #
-    # @param [String] server location
-    # @param [String] server country
+    # @param [String] location of server
+    # @param [String] country of server
     # @return [String] concatenate location and country if not empty
     def country_server_label(location = "", country = "")
       return "" if location.empty? && country.empty?
@@ -724,7 +724,7 @@ def country_server_label(location = "", country = "")
     # each country.
     # @see #MakePoolRecord
     #
-    # @param [Hash <String, String>] known countries
+    # @param [Hash <String, String>] known_countries
     # @return [Array <Hash>] pool records for given countries
     def pool_servers_for(known_countries)
       known_countries.map do |short_country, country_name|