@article{05636665,
title = {Core varieties, extensivity, and rig geometry.},
journal = {Theory and Applications of Categories [electronic only]},
volume = {20},
year = {2008},
pages = {497-503},
zbl = {1210.18012},
language = {en},
url = {http://dml.mathdoc.fr/item/05636665}
}
Lawvere, F.William. Core varieties, extensivity, and rig geometry.. Theory and Applications of Categories [electronic only], Tome 20 (2008) pp. 497-503. http://gdmltest.u-ga.fr/item/05636665/