@article{Berghammer_HS_16,
    author           = {Berghammer, Rudolf and H\"ofner, Peter and Stucke, Insa},
    doi              = {10.1016/j.jlamp.2015.12.001},
    journal          = {Journal of Logical and Algebraic Methods in Programming},
    month            = may,
    number           = {2},
    pages            = {269--286},
    paperurl         = {https://trustworthy.systems/publications/nicta_full_text/8898.pdf},
    title            = {Cardinality of Relations and Relational Approximation Algorithms},
    volume           = {85},
    year             = {2016}
  }