APA (7th ed.) Citation

Ashford,David. (1991). Your spaceflight manual: How you could be a tourist in space within twenty years. Crescent books.

Chicago Style (17th ed.) Citation

Ashford,David. Your Spaceflight Manual: How You Could Be a Tourist in Space Within Twenty Years. NewYork: Crescent books, 1991.

MLA (9th ed.) Citation

Ashford,David. Your Spaceflight Manual: How You Could Be a Tourist in Space Within Twenty Years. Crescent books, 1991.

Warning: These citations may not always be 100% accurate.