Vasco Brattka. Borel complexity and computability of the Hahn-Banach Theorem. Arch. Math. Log., 46(7-8):547-564, 2008. [doi]
@article{Brattka08,
title = {Borel complexity and computability of the Hahn-Banach Theorem},
author = {Vasco Brattka},
year = {2008},
doi = {10.1007/s00153-007-0057-z},
url = {http://dx.doi.org/10.1007/s00153-007-0057-z},
researchr = {https://researchr.org/publication/Brattka08},
cites = {0},
citedby = {0},
journal = {Arch. Math. Log.},
volume = {46},
number = {7-8},
pages = {547-564},
}