@inproceedings{sgem2020s05069,
  title = {GEOMAGNETIC FIELD ELEMENTS OF THE BULGARIAN TERRITORY FOR 2020.0 EPOCH},
  author = {Metodi Metodiev and Petya Trifonova},
  booktitle = {SGEM International Multidisciplinary Scientific GeoConference EXPO Proceedings; 20th International Multidisciplinary Scientific GeoConference Proceedings SGEM 2020, Science and Technologies in Geology, Exploration And Mining},
  year = {2020},
  pages = {543-550},
  publisher = {STEF92 Technology},
  doi = {10.5593/sgem2020/1.2/s05.069}
}