1. Apollo The Epic Journey to the Moon;Reynolds,2002
2. One Giant Leap — Apollo 11 Remembered;Bizony,2009
3. Carrying the Fire;Collins,1974
4. Webster's Third New International Dictionary of the English Language, Merriam–Webster, Springfield, MA, 2002, p. 647.
5. The rocket in India from ‘Ancient Times’ to the 19th century;Winter;JBIS,1979