1. Berroth, A. and Und, W. 1960. Hofmann (.) Kosmische Geodaesie. Karlsruhe, G. Braun.
2. Girnius, A. and Joughin, W. Optical synthetic simultaneous obs, between B-N carera stations. SAO Special Report No. 266.
3. Geodezija, Girnius A. 1985. 185–187. LE 37, Satelitas. P. 517–518