Henry Martyn Mulder, Alexander Schrijver. Median graphs and Helly hypergraphs. Discrete Mathematics, 25(1):41-50, 1979. [doi]
@article{MulderS79,
title = {Median graphs and Helly hypergraphs},
author = {Henry Martyn Mulder and Alexander Schrijver},
year = {1979},
doi = {10.1016/0012-365X(79)90151-1},
url = {http://dx.doi.org/10.1016/0012-365X(79)90151-1},
researchr = {https://researchr.org/publication/MulderS79},
cites = {0},
citedby = {0},
journal = {Discrete Mathematics},
volume = {25},
number = {1},
pages = {41-50},
}