The maintenance and food service workers at Prestigious University are represented by the International Brotherhood of Teamsters Union. The union and the university administration have just agreed on a new collective bargaining agreement covering the next four years. A number of workers in the skilled maintenance department are dissatisfied with their union because they feel that the union accepted lower wage raises in return for getting a long-term contract. They contact a representative of the Service Employees International Union to discuss ousting the Teamsters as their bargaining representative. What must the workers do to get the NLRB to hold a decertification election