ติ๊กจ๊ะ ว.; หน่อใหม่ ฐ.; จิตต์บุรุษ อ.; ภูมิลา อ. PERIODIC WITH PERIOD 4 OF A PIECEWISE LINEAR SYSTEM OF DIFFERENCE EQUATIONS WITH INITIAL CONDITIONS BEING SOME POINTS ON POSITIVE Y AXIS. PSRU Journal of Science and Technology, Phitsanulok, Thailand, v. 3, n. 2, p. 26–34, 2018. Disponível em: https://ph01.tci-thaijo.org/index.php/Scipsru/article/view/125217. Acesso em: 13 aug. 2022.