@article{JSFU_2024_17_3_a8,
     author = {Andrey V. Litavrin},
     title = {On the bipolar classification of endomorphisms of a groupoid},
     journal = {\v{Z}urnal Sibirskogo federalʹnogo universiteta. Matematika i fizika},
     pages = {378--387},
     publisher = {mathdoc},
     volume = {17},
     number = {3},
     year = {2024},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/JSFU_2024_17_3_a8/}
}