@incollection{CalVai:89,
  volume = {379},
  title = {Ehrenfeucht test set theorem and {H}ilbert basis theorem: a
           constructive glimpse},
  year = {1989},
  booktitle = {Mathematical foundations of computer science 1989
               (Porabka-Kozubnik, 1989)},
  pages = {177--184},
  publisher = {Springer},
  address = {Berlin},
  author = {Calude, Cristian and Vaida, Drago\c{s}},
  series = {Lecture Notes in Comput. Sci.},
}