http://books.google.com/books?vid=ISBN978-0-304-35469-6
1407
http://books.google.com/books?vid=ISBN0-304-35469-4
3
http://citation.dbpedia.org/hash/b1db360651636f52baac811425f6e48954b0ca159938689d5724ce4466369610
1
http://ru.wikisource.org/wiki/На_Луне_(Циолковский)
1