Management of sepsis in neutropenic patients: guidelines from the infectious diseases working party of the German Society of Hematology and Oncology - Penack, O; Buchheidt, D; Christopeit, M; von Lilienfeld-Toal, M; Massenkeil, G; Hentrich, M; Salwender, H; Wolf, H H; Ostermann, H (Ann Oncol, 2011)