NEW YORK - The law firm representing the lead plaintiffs in a class action against General Motors on May 15 sent a letter to the bankruptcy judge in the U.S. Bankruptcy Court for the Southern District of New York presiding over the Chapter 11 case of GM, contending that the Bankruptcy Court should stay an asset sale order (In Re: Motors Liquidation Company, No. 09-50026, Chapter 11, S.D. N.Y. Bkcy.).