@inproceedings(1997-gram-ticas-datalog-extendidas-una-nueva-aproximaci-n,
  author = {Lidia Ana Moreno Boronat and Manuel Palomar and Antonio Molina Marco},
  title = {Gramáticas Datalog Extendidas: una nueva aproximación},
  year = {1997},
  booktitle = {Joint Conference on Declarative Programming (APPIA-GULP-PRODE) (Formerly GULP-PRODE and formerly PRODE)},
  address = {Grado, Italia},
  pages = {153-162}
)