I. Introduction
At present, biometric information security technologies are being actively developed, as well as the legal aspects of their application in practice [1]. Traditional methods of document protection do not provide the full level of protection required today [2]. One of the promising methods for protecting important financial, legal and administrative documents from counterfeiting and falsification is the technology of their marking based on a speech signature (SS) [3], [4] or a biosignature (BS) [5].