DALLAS - The body of celebrated auto designer and race car driver Carroll Shelby, who died more than a month ago, could remain in a Dallas morgue for several more weeks while his family fights about burial plans, one of Shelby's sons said Tuesday.

Shelby's three children say their father, who died May 10 in a Dallas hospital, signed a document giving them permission to have his body cremated. But his wife, Cleo Shelby, who lives in California, alleges the signature on that directive is a forgery. She says a document signed two years ago gives her power of attorney in Shelby's affairs.

Both sides have filed documents in a lawsuit pending in Dallas County court. In the meantime, Shelby's body remains in the custody of the Dallas medical examiner's office, which did not immediately return messages seeking comment.

"There's just a lack of closure in a situation where he did have a nice, long life," Patrick Shelby, one of Carroll's sons, told The Associated Press. "He's got relatives down in East Texas, and we're just not able to get this chapter closed. And I'm not really sure what the reasoning is."

Shelby was a champion race car driver who built powerful engines for Ford's Mustang and Chrysler's Viper. His iconic last name is stamped onto dozens of sports car models, including a new Mustang Shelby GT500 that he tested months before his death.

When he died at age 89, Shelby also was one of the nation's longest-living heart transplant recipients and later started the Carroll Shelby Foundation for children and young people needing acute coronary and kidney care.

A one-time chicken farmer, Shelby married several times and kept homes in Los Angeles and his native East Texas.

His sons Patrick and Michael, along with their sister Sharon, say in their lawsuit that their father made his last wishes clear in a document signed this February. That document says his ashes are to be divided equally between his living children and a burial plot in his native East Texas.

Cleo Shelby has filed an affidavit saying her husband gave her power of attorney in August 2010 after he suffered a stroke in Wisconsin.

"My husband informed Michael Shelby that he was going to appoint me as his primary health care agent," Cleo Shelby said in the court filing. "When he did so he said he was designating me because I was always with him, Michael Shelby lived in Texas, and that I had 'saved his life' on several previous occasions."

Cleo Shelby accused Michael Shelby in the court filing of having "arranged to exclude" her from being with her husband "except for a very limited number of occasions" before his death. She declined to be interviewed Tuesday, citing the pending court case.

Michael Shelby did not immediately return a phone message.

No hearings have been scheduled in the case.