Logic problem

I am a huge fan of logic problems. Here is one that took me awhile. Legend has it that it was written by Einstein. The problem goes like this:

• There are five houses lined up next to each other along a street.
• Each house is a different color
• Each homeowner is of a different nationality, drinks a different beverage, smokes a different brand of cigar, and owns a different pet.
• The Englishman lives in the house with red walls.
• The Swede keeps dogs.
• The Dane drinks tea.
• The house with green walls is just to the left of the house with white walls.
• The owner of the house with green walls drinks coffee.
• The man who smokes Pall Mall keeps birds.
• The owner of the house with yellow walls smokes Dunhills.
• The man in the center house drinks milk.
• The Norwegian lives in the first house.
• The Blend smoker has a neighbor who keeps cats.
• The man who smokes Blue Masters drinks beer.
• The man who keeps horses lives next to the Dunhill smoker.
• The German smokes Prince.
• The Norwegian lives next to the house with blue walls.
• The Blend smoker has a neighbor who drinks water.
  
  
  
  The question is: Who owns a pet fish? The answer later this evening…