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- Beukelman, W. (author), de Beer, F. (author) report 1986
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- de Beer, F. (author) report 1985
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- de Beer, F. (author) report 1985
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- de Beer, F. (author) report 1985
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- de Beer, F. (author), Burgel, A.P. (author) report 1985
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- de Beer, F. (author) report 1985
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- de Beer, F. (author) report 1985
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- de Beer, F. (author) report 1984
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- de Beer, F. (author) report 1982
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- Vis, P.A. (author), de Haan, P.J. (author), de Beer, F. (author) report 1981
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- de Beer, F. (author) report 1981
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- Vis, P.A. (author), de Haan, P.J. (author), de Beer, F. (author) report 1981
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- de Beer, Frits (author) report 1972
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- de Beer, Frits (author) report 1971
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- de Beer, Frits (author) report 1971
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- de Beer, Frits (author) report 1971
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- de Beer, Frits (author) report 1971
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- de Beer, Frits (author) report 1969