@article{MAN_1869__1_156406,
     author = {A. Bessel},
     title = {Ueber die {Invarianten} der einfachsten {Systeme} simultaner bin\"arer {Formen.} {Von} {A.} {Bessel} in {St.} {Petersburg}},
     journal = {Mathematische Annalen},
     pages = {173--194},
     publisher = {mathdoc},
     volume = {1},
     year = {1869},
     zbl = {02.0064.02},
     url = {http://geodesic.mathdoc.fr/item/MAN_1869__1_156406/}
}