Liu, F., G.-D. Huang, J.-Z. Tang, and Y.-H. Peng. “DPP4 Inhibitors Promote Biological Functions of Human Endothelial Progenitor Cells by Targeting the SDF-1/CXCR4 Signaling Pathway”. Archives of Biological Sciences, vol. 68, no. 1, June 2016, pp. 207-16, https://serbiosoc.org.rs/arch/index.php/abs/article/view/757.