Primary Sources, WWI Reconnaissance

[fsupilot22]

Hey folks,

I apologize if this is in the wrong forum, but I am searching for primary sources on WWI Aerial Reconnaissance for a research project. There is apparently not much on it at my university and database searches are coming up slim. I have a handful of books that discuss reconnaissance in passing, but none that really address it. I wish I could offer my detail about what I am researching, but to be honest, I am not even quite sure what about aerial reconnaissance I am even trying to answer. Right now, I am just trying to get a start.

Any suggestions on any solid books or articles on the topic would be helpful, primary or secondary.

Thank you.