Khayrullina, Y., M. Eflova, R. Garipova, and E. Yamilov. “The Problems of Development of Small Business: The Experience of Empirical Research (based on the Materials of the Republic of Tatarstan)”. Amazonia Investiga, Vol. 7, no. 17, Dec. 2018, pp. 406-13, https://www.amazoniainvestiga.info/index.php/amazonia/article/view/755.