H. S. Alshawee. 2015. “On the Dynamics of the Nonlinear Rational Difference Equation x_{n+1}=Ax_{n}+Bx_{n-a}+((ax_{n-a}+bx_{n-k}) (cx_{n-a}+dx_{n-k}))”. Global Journal of Science Frontier Research 15 (F9):33-43. https://journalofscience.org/index.php/GJSFR/article/view/102261.