41
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by Martens, Ekkehard
Published 1997
Published 1997
Book
46
47
Article
48
by Gühne, Ekkehard
Published 1978
Published 1978
Book
49
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51
52
53
54
55
56
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58
by Bader, Ekkehard R.
Published 2000
Published 2000
Book
59
Article
60