APA-viite (7. p.)
Otto, M. (2008). Feasibility study and future projections of suborbital space tourism at the example of Virgin Galactic. Diplomica Verlag.
Chicago-viite (17. p.)
Otto, Matthias. Feasibility Study and Future Projections of Suborbital Space Tourism at the Example of Virgin Galactic. Hamburg: Diplomica Verlag, 2008.
MLA-viite (9. p.)
Otto, Matthias. Feasibility Study and Future Projections of Suborbital Space Tourism at the Example of Virgin Galactic. Diplomica Verlag, 2008.
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