Peter Winkler. Puzzled. Communications of the ACM, 54(11):120, 2011. [doi]
@article{Winkler11f,
title = {Puzzled},
author = {Peter Winkler},
year = {2011},
doi = {10.1145/2018396.2018422},
url = {http://doi.acm.org/10.1145/2018396.2018422},
researchr = {https://researchr.org/publication/Winkler11f},
cites = {0},
citedby = {0},
journal = {Communications of the ACM},
volume = {54},
number = {11},
pages = {120},
}