Estrada Loya CA, Villarreal Ballesteros AC. Challenges that contribute to the formation process of primary school principals. IE REDIECH [Internet]. 2018Oct.1 [cited 2024May18];9(17):69 - 86. Available from: https://mail.rediech.org/ojs/2017/index.php/ie_rie_rediech/article/view/211