A court in Massachusetts has been asked to stop the sale of 40 works of art that include two by legendary American artist Norman Rockwell.

State Attorney General Maura Healey asked the Massachusetts Appeals Court to halt the sale that’s scheduled to begin Monday so she can appeal an earlier lower court ruling allowing the auction to go ahead by the Berkshire Museum in Pittsfield.

Among those fighting the sale are Rockwell’s three sons who say they want to maintain their father’s wish to keep the artwork in the Berkshires “for all to enjoy.”