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van den Berg M, Piers DA, Zwierstra RP.van den Berg M, et al. Among authors: piers da.Ned Tijdschr Geneeskd. 1987 Aug 15;131(33):1440-2.Ned Tijdschr Geneeskd. 1987.PMID: 3670418Dutch.No abstract available.
de Graaf JS, Klooster NJ, de Lange WE, Piers DA, Zwierstra RP.de Graaf JS, et al. Among authors: piers da.Ned Tijdschr Geneeskd. 1991 Dec 14;135(50):2383-7.Ned Tijdschr Geneeskd. 1991.PMID: 1749444Dutch.
Kloppenburg M, Beekhuis H, Piers DA.Kloppenburg M, et al. Among authors: piers da.Ned Tijdschr Geneeskd. 1980 Aug 2;124(31):1293-8.Ned Tijdschr Geneeskd. 1980.PMID: 7412902Dutch.No abstract available.