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P.P.C. Haanappel, «The transformation of sovereignty in the air». In: The Use of Air and Outer Space Cooperation and Competition: Proceedings of the International Conference on Air and Outer Space at the Service of World Peace and Prosperity, Held in Beijing from 21-23 August 1995. Chia-Jui Cheng (editor), Published by Martinus Nijhoff Publishers, 1998. ISBN 90-411-0597-2, Partial textАрхивная копия от 11 августа 2014 на Wayback Machine on Google Books. Page 23.
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