It's difficult to mention just ONE favorite autograph.

I would like to mention Emperor Bao Dai of Vietnam who was deposed in 1955, a personal letter of Jack Lynch to me explaining the origin of the Irish National Anthem and Nelson Mandela from South Africa. He managed to avoid a bloodshed after the end of Apartheid.

The most beautiful handwriting I have ever seen is that of former Hungarian State President Mátyás Szueroes who wrote the first stanza of the Hungarian National Anthem for me.

And not to forget Mikhail Gorbchev who helped to change the world...

I could write a book on all these items...