&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Acta Astronautica. 1988.<br><br>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Vol. 18 : 38th IAF Congress. 30 Years in Progress in Space. &mdash; 1988. &mdash; ISSN 0094-5765.<br><br><br><br>[ SYS NUM: 9389 ]