Liên quan Robert Oppenheimer Robert Lewandowski Roberto Carlos Robert Downey Jr. Roberto Baggio Roberto Mancini Robert Pattinson Robert Pirès Roberto Firmino Robert Schumann
Tài liệu tham khảo WikiPedia: Robert_H._Goddard http://www.astronautix.com/lvs/goddard.htm http://www.fathom.com/course/21701743/session1.htm... http://sites.google.com/site/rgoddardsite http://www.google.com/patents/about?id=ikBJAAAAEBA... http://www.time.com/time/magazine/article/0,9171,9... http://www.clarku.edu/research/archives/goddard http://www.clarku.edu/research/archives/pdf/ext_al... http://www2.clarku.edu/research/archives/goddard/f... http://www.nasm.si.edu/exhibitions/gal100/goddard.... http://siarchives.si.edu/history/exhibits/document...
