1549	 An Efficient Machine-Independent Procedure for Garbage Collection in Various List Structures	 A method for returning registers to the free list is an essential part of any list processing system. In this paper past solutions of the recovery problem are reviewed and compared. A new algorithm is presented which offers significant advantages of speed and storage utilization. The routine for implementing this algorithm can be written in the list language with which it is to be used thus insuring a degree of machine independence. Finally the application of the algorithm to a number of different list structures appearing in the literature is indicated.
