Vikman, Sofia, Roberta Sommaggio, Manuel De La Torre, Kjell Öberg, Magnus Essand, Valeria Giandomenico, Angelica Loskog, and Thomas H. Tötterman. 2009. “Midgut Carcinoid Patients Display Increased Numbers of Regulatory T Cells in Peripheral Blood With Infiltration into Tumor Tissue”. Acta Oncologica 48 (3):391-400. https://doi.org/10.1080/02841860802438495.