Deumlich, F., & Faig, W. (1982). Surveying instruments. W. de Gruyter.
Lua i Stíl Chicago (17ú heag.)Deumlich, Fritz, agus Wolfgang Faig. Surveying Instruments. Berlin ; New York: W. de Gruyter, 1982.
Lua MLA (9ú heag.)Deumlich, Fritz, agus Wolfgang Faig. Surveying Instruments. W. de Gruyter, 1982.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.