Paul Detlefsen "Horse and Buggy Days"

I have a 36" wide, 24" tall, Paul Detlefsen "Horse and Buggy Days" painting- probably a print? It is in a wooden frame with a metal nameplate at the bottom of the frame. The nameplate says "Horse and Buggy Days" with Paul Detlefsen underneath that. The painting is in excellent condition. On the back of the painting there are 2 stickers: one says Illinois Moulding Co., Chicago, Illinois, with the numbers P155 and underneath that V1583-102. Underneath the numbers it says "Horse and Buggy Days". The signature on the front of the painting: the "P" in Paul is in bright reddish-orange print, as is the "D" in the last name. The other letters are black.

If anyone can give me more information on this painting, I would certainly appreciate it. Is the painting of any value, or a great painting that should be held on to? Is there any way to tell when this print was made? And how do you tell an original from a print?  Thanks to anyone who reads this and can help me out!

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