How do I determine the value of an old oil painting?

I purchased an old oil painting canvas at a garage sale a few years ago. I is signed by the famous artist and have a letter followed by 4 numbers on the back of it. The name of the artist was Andreas Gyula Bubarnik. I want to know if the image is worth something.

Auction houses Sotheby's will be considered, such as paints.

ABC Products - Antique Style ~ Clamp-on-Railing ~ Steel Tiki Torch (Matte Black) $16.47 36 in. antique style steel tiki torch deck mount matte black ~~ Screw type non-abrasive clamp ~~ Weather-resistant coating ~~ For use with citronnella oil ~ outdoor use only....

12 York Bronze Ball Lyra Shower Curtain Hooks Bathroom $9.99 A quick and easy way to bring new life to tired bathroom decor ! This set of 12 shower curtain hooks boasts a clean, basic style and a beautiful bronze finish to give you an expensive designer look at a fraction of the cost. Set of 12. Metal with a bronze finish. Each hook measures approximately 3" L and is nicely weighted....

Glass Shelf - Brushed Nickel (Brushed Nickel) (3.5H x 20.5W x 4.75D) $12.39 Decorate the walls of your home with this one of a kind glass shelf. Easily mount this piece to your wall to hold candles, incense, trinkets picture frames and more and create a clean and stylish atmosphere. This shelf's metal frame is available in a Brushed Nickel or Oil Rubbed Bronze finish. Assembly level/degree of difficulty: Easy....

Movie Classics $22.99 BRIGHT DOUBLE NEON CLOCKS with a color neon tube on the outside and a white neon color tube in the inside, with tin sign advertisement inside! Chrome finish metal case, 12v adapter included and the clock is battery operated. (Battery not included) Good for Kids room, Recreation rooms, Restaurants, Diners, Bars, Game rooms, Garages and anyplace in the home! Available colors: Red, Blue, Orange, Gree...

Royce Lighting RSL01-23 Indoor/Outdoor Ten-Light String Lantern Oil Rubbed Bronze $12.23 Amazing, traditional, old-world, antique style is yours for the taking! Prepare yourself for the look, the style, and the experience that this delightful Ten Light Outdoor String Lantern set will bring your home! Bathed in a rich finish, powerfully constructed from metal, up to three sets can be connected together! Features an On/Off switch. Uses 10 7 watt bulbs, included! Available in your c...

Discovering Oil Lamps (Paperback) $10.64 This book traces the design and evolution of oil lighting, examining in detail the varieties and design features of many of the lamps which were made particularly in the Victorian period. A great many of these lamps still survive today, either conve...

Fontaine Antique Copper 4-hole Kitchen Faucet $117.99 Fontaine kitchen faucet comes complete with a matching sidespray and deck-mount soap dispenserKitchen faucet features 4-hole applicationFaucet offers advanced European styling in antique brushed copper or oil-rubbed bronze

Dottingham Counter-top Soap and Lotion Dispenser $37.99 Enhance your bathroom or kitchen decor with a Dottingham soap/lotion dispenserCountertop dispenser crafted of solid brass Home accessory available in satin nickel, polished chrome, oil rubbed bronze and antique bronze color options

Moen Kingsley 24-inch Oil Rubbed Bronze Finish Towel Bar $39.99 This towel bar by Moen Kingsley offers an elegant oil rubbed bronze finish for a traditional look. By combining a classic antique look with modern luxury, this towel bar offers the best of both worlds.

Solid Brass Vanity Makeup Mirror $67.99 Enhance your bathroom decor with this vanity makeup mirrorDuel sided magnifying mirror made of solid brassSolid brass bathroom accessory is available in antique brass, satin nickel, polished chrome and oil rubbed bronze and color options