Hi there,  I just wanted to mention the following:

The right spelling of the name is Decap, but -- indeed -- Mr. Decap used
DeCap and De Cap (and I've also seen De cap) on his music books and
rolls.

There has been a lot of confusion about his name, and as a result, the
spelling DeCap was even used on the passport of the Decap family (as
Mr. Mostmans, who leads the factory now, told me about four years ago).

Any comments are still welcome !

Greetings,

Bjorn Isebaert