Theory and practice of piano tuning by Brian Capleton

[david at piano.plus.com]

I posted about this book and a regulation book also by Dr. Capleton a few
months ago, I think it might have been under the topic "Two new books". 
Even included a pic!

It's an interesting book, almost philosophical, but as you note, Kurt,
expensive to get one sent to the US.

If you have any specific questions about it, let me know, and I will try
to answer.

Best,

David.