SpringerLink (Online service), Plag, H., & Pearlman, M. (2009). Global geodetic observing system: Meeting the requirements of a global society on a changing planet in 2020. Springer.
Chicago-viite (17. p.)SpringerLink (Online service), Hans-Peter Plag, ja Michael Pearlman. Global Geodetic Observing System: Meeting the Requirements of a Global Society on a Changing Planet in 2020. Berlin, Heidelberg: Springer, 2009.
MLA-viite (8. p.)SpringerLink (Online service), et al. Global Geodetic Observing System: Meeting the Requirements of a Global Society on a Changing Planet in 2020. Springer, 2009.
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