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@Book{            book:675690,
  Author        = "Feynman, Richard P. and Leighton, Robert B. and Sands, Matthew",
  date-added    = "2020-04-10 11:07:26 +0200",
  date-modified = "2020-04-10 11:07:26 +0200",
  Edition       = "Fourth Edition",
  ISBN          = "0465025269,9780465025268",
  Publisher     = "Basic Books",
  Title         = "Six Not-So-Easy Pieces: Einstein's Relativity, Symmetry, and Space-Time",
  URL           = "http://gen.lib.rus.ec/book/index.php?md5=802AA421C926121251E3394BB514ECD5",
  Year          = "2011",
  bdsk-url-1    = "http://gen.lib.rus.ec/book/index.php?md5=802AA421C926121251E3394BB514ECD5",
  File          = "Richard P. Feynman, Robert B. Leighton, Matthew Sands-Six Not-So-Easy Pieces\_ Einstein's Relativity, Symmetry, and Space-Time-Basic Books (2011) (0) - a - a.epub"
}

@Book{ book:675690, Author = "Feynman, Richard P. and Leighton, Robert B. and Sands, Matthew", date-added = "2020-04-10 11:07:26 +0200", date-modified = "2020-04-10 11:07:26 +0200", Edition = "Fourth Edition", ISBN = "0465025269,9780465025268", Publisher = "Basic Books", Title = "Six Not-So-Easy Pieces: Einstein's Relativity, Symmetry, and Space-Time", URL = "http://gen.lib.rus.ec/book/index.php?md5=802AA421C926121251E3394BB514ECD5", Year = "2011", bdsk-url-1 = "http://gen.lib.rus.ec/book/index.php?md5=802AA421C926121251E3394BB514ECD5", File = "Richard P. Feynman, Robert B. Leighton, Matthew Sands-Six Not-So-Easy Pieces_ Einstein's Relativity, Symmetry, and Space-Time-Basic Books (2011) (0) - a - a.epub" }