@article{DMGAA_2024_44_1_a7,
     author = {Schwab, Emil Daniel},
     title = {A bisimple inverse monoid of quadruples of non-negative integers. {The} {M\"obius} function},
     journal = {Discussiones Mathematicae. General Algebra and Applications},
     pages = {111--126},
     publisher = {mathdoc},
     volume = {44},
     number = {1},
     year = {2024},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/DMGAA_2024_44_1_a7/}
}