@article{ADM_2018_26_2_a7,
     author = {Anatolii V. Zhuchok and Kolja Knauer},
     title = {Abelian doppelsemigroups},
     journal = {Algebra and discrete mathematics},
     pages = {290--304},
     publisher = {mathdoc},
     volume = {26},
     number = {2},
     year = {2018},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/ADM_2018_26_2_a7/}
}