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- van Leeuwen, Ger (author) report 1971
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- van Leeuwen, Ger (author) report 1970
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- van Leeuwen, Ger (author) report 1969
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- van Leeuwen, Ger (author) report 1967
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- Nibbering, J.J.W. (author), van Leeuwen, R.T. (author) report 1965
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- van Leeuwen, Ger (author) report 1964
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- van Leeuwen, Ger (author) report 1963
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- van Leeuwen, Ger (author) report 1962
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- van Leeuwen, Ger (author) report 1960