Stanley U. Robinson, Robert W. House. Gimpel's Reduction Technique Extended to the Covering Problem with Costs. IEEE Transactions on Computers, 16(4):509-514, 1967. [doi]
@article{RobinsonH67,
title = {Gimpel's Reduction Technique Extended to the Covering Problem with Costs},
author = {Stanley U. Robinson and Robert W. House},
year = {1967},
doi = {10.1109/PGEC.1967.264675},
url = {http://dx.doi.org/10.1109/PGEC.1967.264675},
researchr = {https://researchr.org/publication/RobinsonH67},
cites = {0},
citedby = {0},
journal = {IEEE Transactions on Computers},
volume = {16},
number = {4},
pages = {509-514},
}