Martin Knor, Ludovít Niepel. Radii and centers in iterated line digraphs. Discussiones Mathematicae Graph Theory, 16(1):17-26, 1996. [doi]
@article{KnorN96,
title = {Radii and centers in iterated line digraphs},
author = {Martin Knor and Ludovít Niepel},
year = {1996},
doi = {10.7151/dmgt.1020},
url = {http://dx.doi.org/10.7151/dmgt.1020},
researchr = {https://researchr.org/publication/KnorN96},
cites = {0},
citedby = {0},
journal = {Discussiones Mathematicae Graph Theory},
volume = {16},
number = {1},
pages = {17-26},
}