G. Gergov, M. Alexieva, E. Mekov, N. Yanev, R. Petkov, and G. Yankov, “Synchronous primary atypical pulmonary carcinoid and cecal adenocarcinoma: a case report”, AMB, vol. 53, no. 3, pp. 61–67, Sep. 2026, doi: 10.2478/AMB-2026-0074.