Where Can I Learn About Prandtl's Theory on Aircraft Footprints?

[Raptor01601]

Does anybody know of a book that addreses/talks about how Prandtl showed that an aircraft passing overhead will leave a "footprint" on the Earth in the form of an extremely small pressure change over a huge area?

 

[Danger]

There's a thread about that around here somewhere, from maybe a month or so back.