@book{lukens_schmitt_broucek_1961, 
  title={APPROXIMATE TRANSFER FUNCTIONS FOR FLEXIBLE-BOOSTER-AND AUTOPILOT ANALYSIS}, 
  DOI={10.21236/ad0269015}, 
  institution={Defense Technical Information Center}, 
  author={LUKENS and SCHMITT and BROUCEK}, 
  year={1961}, 
  month={Apr}
  }