Statistical controversies in clinical research: requiem for the 3 + 3 design for phase I trials. Paoletti, X.; Ezzalfani, M.; Le Tourneau, C.. Ann Oncol. 2015; 1808-12: p.1808-12. doi:10.1093/annonc/mdv266 10.1093/annonc/mdv266. Epub 2015 Jun 18.Article