On a decoding algorithm for codes on maximal curves

A decoding algorithm for algebraic geometric codes that was given by A.N. Skorobogatov and S.G. Vladut (preprint, Inst. Problems of Information Transmission, 1988) is considered. The author gives a modified algorithm, with improved performance, which he obtains by applying the above algorithm a number of times in parallel. He proves the existence of the decoding algorithm on maximal curves by showing the existence of certain divisors. However, he has so far been unable to give an efficient procedure of finding these divisors.>