@article{SIGMA_2021_17_a99,
     author = {Oliver Schnetz and Karen Yeats},
     title = {$c_2$ {Invariants} of {Hourglass} {Chains} via {Quadratic} {Denominator} {Reduction}},
     journal = {Symmetry, integrability and geometry: methods and applications},
     year = {2021},
     volume = {17},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/SIGMA_2021_17_a99/}
}