README.md in czech_names_vocative-0.2.0 vs README.md in czech_names_vocative-0.3.0

@@ -21,15 +21,19 @@
 ## Usage
 
 ```ruby
 "Josef".vocative #=> "Josefe"
 "Petr".vocative #=> "Petře"
-"NonExistingName".vocativ! #=> nil
+"NonExistingName".vocative! #=> nil
 
 "Josef".vocative! #=> "Josefe"
 "Petr".vocative! #=> "Petře"
 "NonExistingName".vocative! #=> "NonExistingName"
 ```
+
+## Known limitations
+
+There can be names which have different vocative for female and male variant (e.g. [Dagmar](http://krestni-jmena.cz/vyznam/index.php?name=Dagmar)), gem will simply returns the last one in db.
 
 ## Database
 
 Thanks for database to validace.cz
 http://blog.trixi.cz/2012/08/5-pady-vsech-jmen-osob-v-cr-volne-ke-stazeni/