Sample size calculation in clinical trials: part 13 of a series on evaluation of scientific publications
Deutsches Ärzteblatt international (2010) - Comment
pubmed: 20827353  doi: 10.3238/arztebl.2010.0552  issn: 1866-0452 

Bernd Röhrig, Jean-Baptist Du Du Prel, Daniel Wachtlin, Robert Kwiecien, Maria Blettner