1. Proton Beam Therapy in Gastrointestinal Cancers: A Paradigm Shift in Radiotherapy
   Ashwathy Susan Mathew et al, 2022, GI Surgery Annual CrossRef
2. Proton Beam Reirradiation
   Mark W. McDonald et al, 2016, Re-Irradiation: New Frontiers CrossRef
3. Advances in Radiation Therapy for Gastrointestinal Cancers
   Rachit Kumar et al, 2019, Textbook of Gastrointestinal Oncology CrossRef
4. Comparison of dosimetries of carbon-ion pencil beam scanning, proton pencil beam scanning and volumetric modulated arc therapy for locally recurrent rectal cancer
   Shinichiro Mori et al, 2023, Journal of Radiation Research CrossRef