Willett, C., Ajani, J., Kelsen, D., Sigurdson, E., Abrams, R., Berkey, B., … Radiation Therapy Oncology Group, . (2001). Radiation Therapy Oncology Group. Research Plan 2002-2006. Gastrointestinal Cancer Committee. Int J Radiat Oncol Biol Phys, 51(3 Suppl 2), 19–27.

Willett, C., J. Ajani, D. Kelsen, E. Sigurdson, R. Abrams, B. Berkey, M. Benetz, et al. “Radiation Therapy Oncology Group. Research Plan 2002-2006. Gastrointestinal Cancer Committee.” Int J Radiat Oncol Biol Phys 51, no. 3 Suppl 2 (2001): 19–27.

Willett C, Ajani J, Kelsen D, Sigurdson E, Abrams R, Berkey B, et al. Radiation Therapy Oncology Group. Research Plan 2002-2006. Gastrointestinal Cancer Committee. Int J Radiat Oncol Biol Phys. 2001;51(3 Suppl 2):19–27.

Willett, C., et al. “Radiation Therapy Oncology Group. Research Plan 2002-2006. Gastrointestinal Cancer Committee.” Int J Radiat Oncol Biol Phys, vol. 51, no. 3 Suppl 2, 2001, pp. 19–27.

Willett C, Ajani J, Kelsen D, Sigurdson E, Abrams R, Berkey B, Benetz M, Crane C, Gaspar L, Goodyear MD, Gunderson L, Haddock M, Hoffmann J, Janjan N, John M, Kachnic L, Krieg R, Landry J, Meropol N, Minsky B, Mitchell E, Mohiuddin M, Moulder J, Myerson R, Noyes D, Pajak TF, Raben D, Regine W, Rich T, Robertson JM, Russell A, Skibber J, Kim P, Radiation Therapy Oncology Group. Radiation Therapy Oncology Group. Research Plan 2002-2006. Gastrointestinal Cancer Committee. Int J Radiat Oncol Biol Phys. 2001;51(3 Suppl 2):19–27.