Ron Breukelaar, Erik D. Demaine, Susan Hohenberger, Hendrik Jan Hoogeboom, Walter A. Kosters, David Liben-Nowell. Tetris is hard, even to approximate. Int. J. Comput. Geometry Appl., 14(1-2):41-68, 2004. [doi]
@article{BreukelaarDHHKL04,
title = {Tetris is hard, even to approximate},
author = {Ron Breukelaar and Erik D. Demaine and Susan Hohenberger and Hendrik Jan Hoogeboom and Walter A. Kosters and David Liben-Nowell},
year = {2004},
doi = {10.1142/S0218195904001354},
url = {http://dx.doi.org/10.1142/S0218195904001354},
researchr = {https://researchr.org/publication/BreukelaarDHHKL04},
cites = {0},
citedby = {0},
journal = {Int. J. Comput. Geometry Appl.},
volume = {14},
number = {1-2},
pages = {41-68},
}