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@Book{            OppenheimSchafer:DSP:1975,
  Author        = "Oppenheim, Alan V. and Schafer, Ronald W.",
  date-added    = "2021-12-27 11:54:37 +0100",
  date-modified = "2021-12-27 11:54:47 +0100",
  Edition       = "1",
  ISBN          = "0132146355,9780132146357",
  Publisher     = "Prentice-Hall",
  Title         = "Digital Signal Processing",
  URL           = "http://gen.lib.rus.ec/book/index.php?md5=825093F905537F23EE1D5E2D4937FC5F",
  Year          = "1975",
  bdsk-url-1    = "http://gen.lib.rus.ec/book/index.php?md5=825093F905537F23EE1D5E2D4937FC5F",
  File          = "Digital Signal Processing by Alan V. Oppenheim, Ronald W. Schafer (z-lib.org).pdf"
}

@Book{ OppenheimSchafer:DSP:1975, Author = "Oppenheim, Alan V. and Schafer, Ronald W.", date-added = "2021-12-27 11:54:37 +0100", date-modified = "2021-12-27 11:54:47 +0100", Edition = "1", ISBN = "0132146355,9780132146357", Publisher = "Prentice-Hall", Title = "Digital Signal Processing", URL = "http://gen.lib.rus.ec/book/index.php?md5=825093F905537F23EE1D5E2D4937FC5F", Year = "1975", bdsk-url-1 = "http://gen.lib.rus.ec/book/index.php?md5=825093F905537F23EE1D5E2D4937FC5F", File = "Digital Signal Processing by Alan V. Oppenheim, Ronald W. Schafer (z-lib.org).pdf" }