Vaidya, A. M., and V. S. Joshi. “On Exponentially Ternary 2-Free Integers”. The Journal of the Indian Mathematical Society 57, no. 1-4 (December 1, 1991): 169–177. Accessed November 7, 2024. https://informaticsjournals.co.in/index.php/jims/article/view/21940.