Graham Hutton. The countdown problem. Journal of Functional Programming, 12(6):609-616, 2002. [doi]
@article{Hutton02:0, title = {The countdown problem}, author = {Graham Hutton}, year = {2002}, doi = {10.1017/S0956796801004300}, url = {http://dx.doi.org/10.1017/S0956796801004300}, researchr = {https://researchr.org/publication/Hutton02%3A0}, cites = {0}, citedby = {0}, journal = {Journal of Functional Programming}, volume = {12}, number = {6}, pages = {609-616}, }