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In this paper, methods for document retrieval are derived from algebraic coding theory. It is shown that these methods are efficient in information representation and that the amount of computation required in implementation is quite reasonable.

Described in this report are the results of a comprehensive technical survey of all published Soviet literature in coding theory and its applications--over 400 papers and books appearing before March 1967. The purpose of this report is to draw attention to this important collection of technical results, which are not well known in the West, and to summarize the significant contributions. Particular emphasis is placed upon those results that fill gaps in the body of knowledge about coding theory and practice as familiar to non-Soviet The most noteworthy Soviet contributions have occurred in those areas that deal with codes for the noiseless channel, codes that correct asymmetric errors, decoding for cyclic codes, randomcoding bounds on the amount of computation required, and various application criteria--that is, when to use which code, and how well it performs. Other important but isolated results have been reported on the construction of optimal low-rate codes, bounds on nonrandom codes, linear (continuous) coding, codes for checking arithmetic operations, properties of code polynomials, linear transformations of codes, multiple-burst-correcting codes, special synchronization codes, and certain broad generalizations of the conventional coding problem. Little or no significant work has been done on pseudorandom sequences, unit-distance codes (with one exception), the application of codes to the design of redundant computers and memories, the search for good cyclic codes, and the physical realization of sequential decoding algorithms. Section II of this report is directed to the nonspecialist, and describes the status of the field of coding theory in the Soviet Union, summarizes the major technical results, and compares these with corresponding work in the West. Section III discusses in detail for the coding specialist new theoretical results, details of coding procedures, and analytical tools described in the Soviet literature. A complete bibliography is included.