oai-pmh.md

@@ -83,6 +83,17 @@ To get the Oefos ID the uri has */vocabs/oefos2012* and the id at the end
 ```perl
 if ( ($prefixurl, $number) = $id =~ /(.*)\/vocabs\/oefos2012\/(.*)/ ) {
 ```
+### Media Typ
+The mapping used:
+
+| mime/type       | Vocab          |
+| --------------- | -------------- |
+| audio/mp3       | Audio          |
+| application/pdf | Document       |
+| image/png       | Picture        |
+| video/mp4       | Video          |
+|                 | Misccellaneous |
+
 
 ## Links
 - https://www.openarchives.org/