Before revision: For manufacturing science eleven different classes of flexibility has been identified [Browne, 1984], [Sethi and Sethi, 1990]: Machine flexibility - The different operation types that a machine can perform.
After revision: For manufacturing science eleven different classes of flexibility have been identified [Browne, 1984], [Sethi and Sethi, 1990]: Machine flexibility - The different operation types that a machine can perform.