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	booktitle = {Philosophical dimensions in mathematics education},
	year = {2007},
	pages = {83{\textendash}103},
	publisher = {Springer},
	isbn = {978-0-387-71571-1},
	author = {Heeffer, Albrecht},
	editor = {Fran{\c c}ois, Karen and Van Bendegem, Jean Paul}
}
@article {VanBendegem1997,
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	journal = {Kritisch Denkerslexicon},
	volume = {23},
	year = {1997},
	pages = {1-14},
	author = {Van Bendegem, Jean Paul}
}
