Ah, sorry for the misunderstanding. Lots of sources for service manuals, here is one.
http://www.powerbookmedic.com/Manuals/13-inch-macbook-manual.pdf
You know, Google is actually a pretty powerful search tool. I see 1.3 million hits in .29 seconds for this one.
Thank you for your post.
Unfortunatelly this is not the correct manual.
I need the official service manual of apple Macbook Air mid 2012.