Go to the author for authorship

[I-V]

You can often hear such an opinion: Thank God the author is alive, he-and confirm that it is his job!

But what if you are absolutely sure of the authorship of the artist (that is really his thing), but it lacks only the signature. And here you are in high spirits go to the author ... but he refuses to acknowledge that the work - it. Though you (and he!) know exactly what the author - he said.

How to be here? What should I do? And what could be the reasons for this, to put it mildly, an unpleasant situation?

Please tell us would be very grateful.