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@Book{            sparsity,
  date-added    = "2021-09-14 14:09:10 +0200",
  date-modified = "2021-09-14 14:09:19 +0200",
  Title         = "sparsity lecture notes",
  bdsk-url-1    = "https://www.youtube.com/channel/UCXK1OfvHJbSRw0ia1gk2Dag",
  File          = "sparsity2"
}

@Book{ sparsity, date-added = "2021-09-14 14:09:10 +0200", date-modified = "2021-09-14 14:09:19 +0200", Title = "sparsity lecture notes", bdsk-url-1 = "https://www.youtube.com/channel/UCXK1OfvHJbSRw0ia1gk2Dag", File = "sparsity2" }