@article{CM_1935__1__254_0,
     author = {Baer, Reinhold},
     title = {Der {Kern,} eine charakteristische {Untergruppe}},
     journal = {Compositio Mathematica},
     pages = {254--283},
     publisher = {Johnson Reprint Corporation},
     volume = {1},
     year = {1935},
     zbl = {0009.15504},
     language = {de},
     url = {http://www.numdam.org/item/CM_1935__1__254_0/}
}