Sunday music spot: Toccata and Fugue in D Minor (Bach)
"A GA GFED C# D
And she responds, "Toccata and Fugue in D Minor by Bach."
Took me a moment to work it out but the letters on the card do indeed represent the notes of the first few bars of that Toccata.
I'm having great difficulty at the moment persuading blogger's server to upload new images but here is the Toccata and Fugue.