Thomas Zaslavsky. The projective-planar signed graphs. Discrete Mathematics, 113(1-3):223-247, 1993. [doi]
@article{Zaslavsky93,
title = {The projective-planar signed graphs},
author = {Thomas Zaslavsky},
year = {1993},
doi = {10.1016/0012-365X(93)90518-X},
url = {http://dx.doi.org/10.1016/0012-365X(93)90518-X},
tags = {planar graph, graph-rewriting, rewriting},
researchr = {https://researchr.org/publication/Zaslavsky93},
cites = {0},
citedby = {0},
journal = {Discrete Mathematics},
volume = {113},
number = {1-3},
pages = {223-247},
}