Freek Wiedijk. Is ZF a hack?: Comparing the complexity of some (formalist interpretations of) foundational systems for mathematics. J. Applied Logic, 4(4):622-645, 2006. [doi]
@article{Wiedijk06,
title = {Is ZF a hack?: Comparing the complexity of some (formalist interpretations of) foundational systems for mathematics},
author = {Freek Wiedijk},
year = {2006},
doi = {10.1016/j.jal.2005.10.011},
url = {http://dx.doi.org/10.1016/j.jal.2005.10.011},
researchr = {https://researchr.org/publication/Wiedijk06},
cites = {0},
citedby = {0},
journal = {J. Applied Logic},
volume = {4},
number = {4},
pages = {622-645},
}