A will signed by Michael Jackson in 2002 was filed in Los Angeles Superior Court on Wednesday, specifying that he wanted his mother to be the guardian of his three children, but if she were to die before him, he asked that singer Diana Ross be appointed.

Despite the filing of the will, which designated an attorney and music- industry executive as executors of the will and estate, a Los Angeles judge ruled Wednesday that Jackson’s mother will remain the special administrator of the singer’s estate pending another hearing Monday.

Los Angeles Superior Court Judge Mitchell Beckloff said he saw no urgency to remove Katherine Jackson for now, and said he wanted to see if additional wills are filed between now and Monday.

Beckloff said he named Katherine Jackson special administrator three days ago in large part to protect her son’s memorabilia, which recently was the subject of an attempted auction and a lawsuit before the dispute was settled out of court.

During Wednesday’s hearing, Beckloff said the Jackson case was not an ordinary probate matter.

“I think we have a unique case here because the world knows that Michael Jackson has died,’’ Beckloff said. “Clearly we are dealing with an international star.’’

The will names attorney John Branca and music executive John McClain as executors. Through their attorney, Paul G. Hoffman, they sought to have Monday’s order naming Jackson’s mother special administrator vacated, saying it was based on the false assumption the entertainer had no will.

“There is a fundamental problem with that order,’’ Hoffman argued.

According to the five-page will and a series of probate documents filed with it, Jackson’s estate is believed to be worth more than $500 million. The singer, who died Thursday at age 50, left his holdings to the Michael Jackson Family Trust, and he named his mother and children as beneficiaries.

The will was signed by Jackson on July 7, 2002. In it, he names Branca, McClain and his accountant, Barry Siegel, as executors. In a letter dated Aug. 26, 2003, however, Siegel resigned as a co-executor of the will.

In the will, Jackson specifically leaves his former wife, Deborah Rowe, out of any inheritance.

“I have intentionally omitted to provide for my former wife, Deborah Jean Rowe Jackson,’’ the will states.

In a statement, Branca and McClain said the most critical part of the will is his desire that his mother become the guardian of his children.

“As we work to carry out Michael’s instructions to safeguard both the future of his children as well as the remarkable legacy he left us as an artist we ask that all matters involving his estate be handled with the dignity and the respect that Michael and his family deserve,’’ they said.

Jackson, 50, was pronounced dead Thursday at Ronald Reagan UCLA Medical Center, about two hours after he collapsed at his rented Holmby Hills estate, where he was preparing for 50 sold-out concerts in London.

On Monday, Beckloff granted temporary custody of the children — Prince Michael Jr., 12; Paris Michael Katherine, 11; and Prince Michael II, 7 — to Jackson’s 79-year-old mother.

Court papers filed on behalf of Katherine Jackson indicated that the family’s lawyers were unaware of the existence of a will, but they said it was possible that someone will emerge claiming to have one. That happened Tuesday when the 2002 will was turned over to the Jackson family.

Funeral arrangements for Jackson still have not been announced. Rumors circulated Tuesday that Jackson’s body would be transported to Neverland Ranch in Santa Barbara County, with public and private memorial services planned over the weekend.

But in a statement issued by the family’s newly hired spokesman — New York public relations executive Ken Sunshine — the Jacksons said “there will be no public or private viewing at Neverland. Plans are under way regarding a public memorial for Michael Jackson, and we will announce those plans shortly.’’

The Los Angeles Times quoted an unnamed source saying a memorial might be held at Staples Center, where Jackson had been rehearsing for his London concerts.

Meanwhile, a London woman who had earlier claimed to the mother of Jackson’s three children filed 93 pages of court documents claiming that she was still married to the singer. Nona Jackson had sought multiple times in 2007 to have a say in the custody/visitation agreement between Jackson and Rowe, but she was rebuffed each time.

In her papers filed Wednesday, Nona Jackson maintains that she married the singer in 1970, when he was 12 years old. She asks that “all my husband’s properties, monies and assets must be transferred to me immediately.’’

She also requests that Jackson’s body be returned to the coroner’s office.

Nona Jackson states that the entertainer’s three children are hers and that their skin color is fair because she is “originally of white skin color, a white Jew and Saudi Arabian mix.’’

The woman asserts that she and Jackson took prescription drugs because they needed them. She also says they both “had detox regularly and at no time did he ever order anyone to pump his stomach,’’ contradicting an assertion made by the former nanny of Jackson’s children.

A hearing on her petition was scheduled for Aug. 19.