@article{DMGAA_2023_43_1_a5,
     author = {Gr\"atzer, George},
     title = {Using the {Swing} {Lemma} and \( {\mathcal{C}_1} \)-diagrams for congruences of planar semimodular lattices},
     journal = {Discussiones Mathematicae. General Algebra and Applications},
     pages = {63--74},
     publisher = {mathdoc},
     volume = {43},
     number = {1},
     year = {2023},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/DMGAA_2023_43_1_a5/}
}