@article{MAN_1996__305_2_165440,
     author = {Paul Schmutz},
     title = {Systoles of arithmetic surfaces and the {Markoff} spectrum.},
     journal = {Mathematische Annalen},
     pages = {191--204},
     publisher = {mathdoc},
     volume = {305},
     number = {2},
     year = {1996},
     zbl = {0853.11054},
     url = {http://geodesic.mathdoc.fr/item/MAN_1996__305_2_165440/}
}