In order for me to properly assess what you have I will need to know the size and see images of the front, back (do not remove from frame) and a clear, in-focus close-up of the signature as well as the authentication.
If you had already attached images to your initial posting, they are not showing for me here on my end.
Please send the photos at your convenience. There is not an extra charge to provide more pictures here.
Depending on which Don Quixote image you have and if it is signed by hand by Dali, these can sell for $100 - $500 on today's auction market. I will be happy to assist further if you can send images here. There is not an additional cost to send photos.
I received your images and thank you for your patience. Dali prints (and others by different artists) with Authenticity certificates from the Collector's Guild are not original prints that were executed by the hand of Dali or signed by Dali. They are 'original' in the sense that they are not modern reproductions, but prints that generally came out of books or portfolios then framed. The average sale price for this image is $75 and the high is $200 - $250. There are some that have paid even more - $300 - $400 for this print, but that is because they were under the impression that this is an original print that Dali personally handled, which is not the case with this image.
Here are some links to comparables for you and their auction sale prices:
Just checking in to see if you viewed your answer and if you are seeking further assistance?
Please let me know.