Peter J. Brown. Note on the proof of the non-existence of a phrase structure grammar for ALGOL 60. Communications of the ACM, 6(3):105, 1963. [doi]
@article{Brown63:0,
title = {Note on the proof of the non-existence of a phrase structure grammar for ALGOL 60},
author = {Peter J. Brown},
year = {1963},
doi = {10.1145/366274.366326},
url = {http://doi.acm.org/10.1145/366274.366326},
tags = {grammar},
researchr = {https://researchr.org/publication/Brown63%3A0},
cites = {0},
citedby = {0},
journal = {Communications of the ACM},
volume = {6},
number = {3},
pages = {105},
}