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Stolk, Pieter, Harald E. Heemstra, Hubert GM Leufkens, Brigitte Bloechl-Daum, and Eibert R. Heerdink. No Difference in Between-country Variability in Use of Newly Approved Orphan and Non- Orphan Medicinal Products - a Pilot Study. BioMed Central, 2009.

Stolk, Pieter, et al. No Difference in Between-country Variability in Use of Newly Approved Orphan and Non- Orphan Medicinal Products - a Pilot Study. BioMed Central, 2009.