Section 17N. Deductions on payroll schedules may be made from the salary of a university of Massachusetts employee of an amount which the employee may specify in writing to the payroll office of the campus where he is employed for payment of certain university sponsored activities. The authorization may be withdrawn by the employee, by giving 60 days notice in writing of the withdrawal to the payroll office where he is employed. The treasurer of the university shall deduct from the salary of the employee the amount of authorized deductions certified to him on the payroll and transmit the sum so deducted to the recipient specified by the employee.