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- contribution to periodical 2017
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- contribution to periodical 2016
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- Nikkels, Thijs (author) contribution to periodical 2016
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- contribution to periodical 2015
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- contribution to periodical 2014
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- contribution to periodical 2013
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- contribution to periodical 2012
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- contribution to periodical 2011
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- contribution to periodical 2009
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- contribution to periodical 2008
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- contribution to periodical 2007
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- contribution to periodical 2006
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- contribution to periodical 2003
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- contribution to periodical 2002
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- contribution to periodical 2001
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- contribution to periodical 2000
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- contribution to periodical 1999
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- contribution to periodical 1968