@article{CaselFernauGaspersetal.2020,
  author    = {Katrin Casel and Henning Fernau and Serge Gaspers and Benjamin Gras and Markus L. Schmid},
  title     = {On the complexity of the smallest grammar problem over fixed alphabets},
  journal   = {Theory of computing systems},
  volume    = {65},
  number    = {2},
  pages     = {344 -- 409},
  doi       = {10.1007/s00224-020-10013-w},
  year      = {2020},
}