Kirov, Todor, Lina Malinova, Dimitrinka Atanasova, and Nikolai Lazarov. “Localization of Substance P-Immunoreactive Nerve Structures in the Rat Colon”. Proceedings of the Bulgarian Academy of Sciences 76, no. 5 (May 29, 2023): 796–802. Accessed December 4, 2023. http://www.proceedings.bas.bg/index.php/cr/article/view/321.