Roberto Tauraso. Problem 11382. The American Mathematical Monthly, 115(7):665, 2008. [doi]
@article{Tauraso08, title = {Problem 11382}, author = {Roberto Tauraso}, year = {2008}, url = {http://www.jstor.org/stable/27642569}, researchr = {https://researchr.org/publication/Tauraso08}, cites = {0}, citedby = {0}, journal = {The American Mathematical Monthly}, volume = {115}, number = {7}, pages = {665}, }