Ole is a farmer in Minnesota. He is in need of a new milk cow and hears about a nice one for sale over in Nordakota. (that would be 'North Dakota' for you non-Scandahoovians out there).
He drives to Nordakota, finds the farm and looks at the cow. Ole reaches under to see if she gives milk. When he grabs the teat and pulls...the cow farts. Ole is very surprised. He looks at the farmer who is selling the cow, then reaches under the cow to try again. He grabs another teat, pulls, and the cow farts again.
Milk does come out however, so after some discussion with the cow's current owner, Ole decides to buy the cow and take it home. When he gets back to Minnesota, he calls over his neighbor, Sven, and says, "Hey, Sven, come and look at dis here new cow I yust bought. Pull her teat, and see vat hoppens."
Sven reaches under, pulls the teat - and the cow farts. Sven looks at Ole and says, "Yah bought dis here cow in Nordakota,didn't yah?" Ole is very surprised since he hadn't told Sven about his trip. Ole replies, "Yah, dats right. But how did you know?" Sven says, "My vife is from Nordakota."