@book {2165,
	title = {Tractatus logico-philosophicus},
	year = {1993},
	publisher = {Gallimard},
	organization = {Gallimard},
	address = {Paris},
	author = {Wittgenstein, Ludwig}
}
@book {2412,
	title = {De la certitude},
	year = {1969},
	publisher = {Gallimard},
	organization = {Gallimard},
	address = {Paris},
	author = {Wittgenstein, Ludwig}
}
