diff --git a/lib/time_calculation.rb b/lib/time_calculation.rb
index f3e4608fc..c09e0c9f4 100644
--- a/lib/time_calculation.rb
+++ b/lib/time_calculation.rb
@@ -1,4 +1,23 @@
 module TimeCalculation
+
+=begin
+
+put working hours matrix and timezone in function, returns UTC working hours matrix
+
+  working_hours_martix = TimeCalculation.working_hours('2013-10-27 20:00:15', working_hours_matrix, 'Europe/Berlin')
+
+  working_hours_martix = {
+    :Mon => [nil,nil,nil,nil,nil,nil,nil,nil,true,true,true,true,true,true,true,true,true,true,true,nil,nil,nil,nil,nil],
+    :Tue => [nil,nil,nil,nil,nil,nil,nil,nil,true,true,true,true,true,true,true,true,true,true,true,nil,nil,nil,nil,nil],
+    :Wed => [nil,nil,nil,nil,nil,nil,nil,nil,true,true,true,true,true,true,true,true,true,true,true,nil,nil,nil,nil,nil],
+    :Thu => [nil,nil,nil,nil,nil,nil,nil,nil,true,true,true,true,true,true,true,true,true,true,true,nil,nil,nil,nil,nil],
+    :Fri => [nil,nil,nil,nil,nil,nil,nil,nil,true,true,true,true,true,true,true,true,true,true,true,nil,nil,nil,nil,nil],
+    :Sat => [],
+    :Sun => [],
+  }
+
+=end
+
   def self.working_hours(start_time, config, timezone)
     time_diff = 0
     if timezone
@@ -77,6 +96,19 @@ module TimeCalculation
     return working_hours
   end
 
+=begin
+
+  returns business hours in minutes between to dates
+
+  business_hours_in_min = Time.Calculation.business_time_diff(
+    '2013-10-27 14:00:15',
+    '2013-10-27 18:10:15',
+    working_hours_martix,
+    'Europe/Berlin',
+  )
+
+=end
+
   def self.business_time_diff(start_time, end_time, config, timezone = '')
     if start_time.class == String
       start_time  = Time.parse( start_time.to_s + 'UTC' )
@@ -180,6 +212,19 @@ module TimeCalculation
     diff.round
   end
 
+=begin
+
+  returns destination date of start time plus X minutes
+
+  dest_time = Time.Calculation.dest_time(
+    '2013-10-27 14:00:15',
+    120,
+    working_hours_martix,
+    'Europe/Berlin',
+  )
+
+=end
+
   def self.dest_time(start_time, diff_in_min, config, timezone = '')
     if start_time.class == String
       start_time = Time.parse( start_time.to_s + ' UTC' )