FARKAS, Ervin; KRAUTER, András; GRACZKA , Gyula. ELECTRONIC SURVEYING INSTRUMENTS FOR MINING PRACTICE Periodica Polytechnica Civil Engineering, [S. l.], v. 21, n. 1-2, p. 69–73, 1977. Disponível em: https://pp.bme.hu/ci/article/view/4167. Acesso em: 15 2025.