“A Cross-Sectional Observational Study to Establish the Association Between ECOG Performance Status and Age and Administration of Doublet or Triplet Chemotherapy Containing Xeloda® (capecitabine) in Advanced Gastric Cancer Patients”. European Journal of Oncology and Environmental Health, vol. 18, no. 4, June 2014, pp. 173-80, https://mattioli1885journals.com/index.php/EJOEH/article/view/2443.