Here is the opinion in City of Duluth vs. Fond du Lac Band of Lake Superior Chippewa Indians. Link to oral argument video here.
Briefs are not available publicly, so if anyone has them, please send along.
Here are the briefs:
When an Indian band enters into a contract with a city, waives its sovereign immunity, and consents to be sued only in federal district court, a state court may go no further than interpreting contractual provisions pertaining to jurisdiction to determine whether the court has jurisdiction over a dispute arising under the contract.
Our post with a link to the Minnesota Court of Appeals decision, now reversed, is here.