Willett CG, Moughan J, O'Meara E, Galvin JM, Crane CH, Winter K, Manfredi D, Rich TA, Rabinovitch R, Lustig R, Machtay M, Curran WJ. Compliance with therapeutic guidelines in Radiation Therapy Oncology Group prospective gastrointestinal clinical trials. Radiother Oncol. 2012 Oct; 105(1):9-13.