Mahmoodi, Mahboobeh, Kalantari, Mina, Mirhaj, Marjan. Effect of Hydroxyapatite Nanoparticles on Differentiotion of Mesenchymal Stem ‍Cells  into Bone cells in Polycaprolacton/Keratin/Hydroxyapatite Scaffolds. Advanced Processes in Materials Engineering. 2020;14(1):55-71. doi: