@article{freuder-1997-holygrail,
  author          = {Eugene C. Freuder},
  title           = {In Pursuit of the Holy Grail},
  journal         = {Constraints An Int. J.},
  volume          = 2,
  number          = 1,
  pages           = {57--61},
  year            = 1997,
  url             = {https://doi.org/10.1023/A:1009749006768},
  doi             = {10.1023/A:1009749006768},
  timestamp       = {Fri, 13 Mar 2020 10:58:24 +0100},
  biburl          = {https://dblp.org/rec/journals/constraints/Freuder97.bib},
  bibsource       = {dblp computer science bibliography, https://dblp.org}
}

@book{marriott-1998-clp,
  location        = {Cambridge, Mass},
  title           = {Programming with constraints: an introduction},
  isbn            = {978-0-262-13341-8},
  shorttitle      = {Programming with constraints},
  pagetotal       = 467,
  publisher       = {{MIT} Press},
  author          = {Marriott, Kim and Stuckey, Peter J.},
  date            = 1998,
  keywords        = {Constraint programming (Computer science), Logic
                  programming},
}

@book{silvano-1990-knapsack,
  author          = {Martello, Silvano and Toth, Paolo},
  title           = {Knapsack Problems: Algorithms and Computer Implementations},
  year            = 1990,
  isbn            = 0471924202,
  publisher       = {John Wiley \& Sons, Inc.},
  address         = {USA}
}