@BOOK{hodges-logic,
  AUTHOR = {Hodges, Wilfred},
  ISBN = {0140136363},
  PUBLISHER = {Penguin},
  TITLE = {Logic: An Introduction to Elementary Logic},
  YEAR = {1977, 1991},
}

@MANUAL{saso-forest-manual,
  AUTHOR = {Živanović, Sašo},
  DATE = {2016-03-04},
  EDITION = {2.0.2},
  KEYWORDS = {TeX, LaTeX, PGF, TikZ, Forest},
  TITLE = {Forest: A {PGF}/Ti\mkbibemph{k}{Z}-Based Package for Drawing Linguistic Trees},
  URL = {http://spj.ff.uni-lj.si/zivanovic/},
}

@MANUAL{tantau-tikz-pgf-manual,
  AUTHOR = {Tantau, Till},
  DATE = {2015-08-29},
  EDITION = {3.0.1a},
  KEYWORDS = {TeX, LaTeX, PGF, TikZ},
  SUBTITLE = {Manual for Version 3.0.1a},
  TITLE = {The {T}i\mkbibemph{k}{Z} and {PGF} Packages},
  URL = {http://sourceforge.net/projects/pgf},
}

