Dylan is known for his protest songs

Junichi Saga was alerted to the fact that words from his book Confessions of a Yakuza could be found in recent Dylan lyrics.

An example of the similarities can be found in the 2001 album track Floaters.

Mr Saga's book contains the lines "I'm not as cool or forgiving as I might have sounded" and "Tears or not, though, that was too much to ask".

The song lyrics contain the lines "I'm not quite as cool or forgiving as I sound" and "Sometimes somebody wants you to give something up, And tears or not, it's too much to ask".

Although Dylan is known to borrow references from art and literature for his lyrics it is not known whether he intentionally used words from Confessions of a Yakuza.

Out of print

"I'm ecstatic that such an influential singer was inspired by what I wrote," said Mr Saga.

But he added he was not particularly familiar with Dylan's music but had since bought an album.

He was surprised to discover, via a Wall Street Journal reporter, that his 1989 book had been used as it had not sold well and was now out of print in Japan.

Mr Saga estimates he earned about 1 million yen (�5,204) from sales of the book.

Mr Saga said that while he would wish to be credited on the song he had "absolutely no plans to sue".

"Why would I sue? To take something that made people around the world happy and try to exploit it for money - that's poverty," he said.