Glad to be of assistance.  I should add that if it is a Holbein, and if it wasn't signed or contained a name of the subject written on it, it could mean that it was used as a study for a further work (i.e. painting).  There may be a Holbein work out there somewhere that was based on your sketch, and someone who is more familiar with Holbein's complete works could possibly make an I.D.  If you want, I can try to give you the name/names of people who could potentially help you.  Also, I'm guessing there might be a catalog of Holbein works available somewhere, and your sketch may be listed in such a catalog.  If so, it would be easier to make an I.D.  If, on the other hand, you have a work of Holbein's that was previously unknown, you would likely have an even rarer (and more surprising) work on your hands which would be rather helpful to art historians...I'm sure a Holbein specialist would offer to help you out in finding information you are searching for.

That would be very helpful. I have been looking trough Holbines work on the net and hve not been able to find thework this sketch is based on. Finding someone that knows Holbine well could really help. Thanks again.

The sketch look very much like his work. The thing that sticks out the most is the eyes and nose. In the paintings and sketches by Hans the eyes and nose are always very distictive.