John McCallum. Maintenance of expert systems: life-cycle validity. SIGART Bulletin, 94:26-27, 1985. [doi]
@article{McCallum85-0,
title = {Maintenance of expert systems: life-cycle validity},
author = {John McCallum},
year = {1985},
doi = {10.1145/1056313.1056316},
url = {http://doi.acm.org/10.1145/1056313.1056316},
researchr = {https://researchr.org/publication/McCallum85-0},
cites = {0},
citedby = {0},
journal = {SIGART Bulletin},
volume = {94},
pages = {26-27},
}