A father and son and they both painted landscapes scenes---city, harbors, etc. The father lived / worked in Naples, Rome and even Paris. The son works out of his own studio in Naples and has had dozens of students and fellow artists that have studied under him. The stamp on the back is the studio stamp. The DeVity studio stamp was used first to stamp the backs of his oil-on-tile works and was then later used to stamp the backs of the studio paintings of both father and son. The signature is closest to the son's signature.
Based on comparisons of the same size and type of scenery, it should estimate in the range of $500 to $800.
Here's the potential bad news and I feel it would be wrong of me not to warn you. The stamp on yours is a the Type 3 stamp that was used by the studio staring in the early 1950s. The problem with that particular style stamp is that it was heavily forged by chinese companies during the 1970s. This was the height of the studios popularity and certain markets found it easy to get on the bandwagon so to speak. They sold in quite a few galleries and shops. They often have an ink-stamped style number and reorder number on the canvas stretchers or frame, but not always. It can be extremely hard to tell the difference in the art work. They often sell in the range of $250 to $350.
Your stamp looks very well done. I don't see any of the usual errors you find in forgeries, so I am honestly hesitant to say that you have a "chinese version". It's the right shape, the words line up, the color is right...etc.
To me, based on what I can see so far and in my opinion (which is just that) is does seem real. I just to be fair and makes sure you were aware. =)
If you're interested in selling it and want to avoid common sites like Ebay, I would contact local art galleries, local auction houses, and even antique shops. You'd be surprised at the art that comes out of antique stores. You might also consider one of the online art sites.Art brokerage
If you go with an auction house, make sure you get an estimate and ask about whether or not they do reserves.
If I can be of any further help or you just need more information, don't hesitate to contact me. I'm more than happy to answer any more questions. Please click accept if I have been of any help, since this is the only way we are compensated by JA.
Thanks and have a great weekend.