1. ** ^  ** [ "spring" ](https://www.oed.com/view/Entry/187725) . _[ Oxford English Dictionary ](/wiki/Oxford_English_Dictionary "Oxford English Dictionary") _ (Online ed.). [ Oxford University Press ](/wiki/Oxford_University_Press "Oxford University Press") .  (Subscription or [ participating institution membership ](https://www.oed.com/public/login/loggingin#withyourlibrary) required.)  V. 25. 
  2. ** ^  ** [ Springs ](http://www.madehow.com/Volume-6/Springs.html) How Products Are Made, 14 July 2007. 
  3. ^  _**a** _ _**b** _ White, Lynn Jr. (1966).  [ _Medieval Technology and Social Change_ ](https://archive.org/details/medievaltechnolo00whit) . New York: Oxford Univ. Press. pp. 126–27. [ ISBN ](/wiki/ISBN_\(identifier\) "ISBN \(identifier\)") [ 0-19-500266-0  ](/wiki/Special:BookSources/0-19-500266-0 "Special:BookSources/0-19-500266-0") . 
  4. ** ^  ** Usher, Abbot Payson (1988). [ _A History of Mechanical Inventions_ ](https://books.google.com/books?id=xuDDqqa8FlwC&pg=PA305) . Courier Dover. p. 305. [ ISBN ](/wiki/ISBN_\(identifier\) "ISBN \(identifier\)") [ 0-486-25593-X  ](/wiki/Special:BookSources/0-486-25593-X "Special:BookSources/0-486-25593-X") . 
  5. ** ^  ** Dohrn-van Rossum, Gerhard (1998). [ _History of the Hour: Clocks and Modern Temporal Orders_ ](https://books.google.com/books?id=53K32RiEigMC&pg=PA121) . Univ. of Chicago Press. p. 121. [ ISBN ](/wiki/ISBN_\(identifier\) "ISBN \(identifier\)") [ 0-226-15510-2  ](/wiki/Special:BookSources/0-226-15510-2 "Special:BookSources/0-226-15510-2") . 
  6. ** ^  ** [ Constant Springs ](http://www.pipingtech.com/products/constant-springs.htm) Piping Technology and Products, (retrieved March 2012) 
  7. ** ^  ** [ Variable Spring Supports ](http://www.pipingtech.com/products/variable-springs.htm) Piping Technology and Products, (retrieved March 2012) 
  8. ** ^  ** [ "Springs with dynamically variable stiffness and actuation capability" ](https://patents.google.com/patent/WO2017077541A9/en) . 3 November 2016  . Retrieved  20 March  2018  – via google.com.  ` {{ [ cite journal ](/wiki/Template:Cite_journal "Template:Cite journal") }} ` :  Cite journal requires ` |journal= ` ( [ help ](/wiki/Help:CS1_errors#missing_periodical "Help:CS1 errors") ) 
  9. ** ^  ** [ "Door Lock Springs" ](https://www.springmasters.com/sp/door-lock-springs.html) . _www.springmasters.com_ . Retrieved  20 March  2018  . 
  10. ** ^  ** Edwards, Boyd F. (27 October 2017). [ _The Ideal Spring and Simple Harmonic Motion_ ](https://www.youtube.com/watch?v=zoGL52P5VWo) (Video)  . Utah State University – via YouTube.  Based on  Cutnell, John D.; Johnson, Kenneth W.; Young, David; Stadler, Shane (2015). "10.1 The Ideal Spring and Simple Harmonic Motion". _Physics_ . Hoboken, NJ: Wiley. [ ISBN ](/wiki/ISBN_\(identifier\) "ISBN \(identifier\)") [ 978-1-118-48689-4  ](/wiki/Special:BookSources/978-1-118-48689-4 "Special:BookSources/978-1-118-48689-4") . [ OCLC ](/wiki/OCLC_\(identifier\) "OCLC \(identifier\)") [ 892304999 ](https://www.worldcat.org/oclc/892304999) . 
  11. ** ^  ** Samuel, Andrew; Weir, John (1999).  [ _Introduction to engineering design: modelling, synthesis and problem solving strategies_ ](https://archive.org/details/introductiontoen00samu) (2 ed.). Oxford, England: Butterworth. p. [ 134 ](https://archive.org/details/introductiontoen00samu/page/n138) . [ ISBN ](/wiki/ISBN_\(identifier\) "ISBN \(identifier\)") [ 0-7506-4282-3  ](/wiki/Special:BookSources/0-7506-4282-3 "Special:BookSources/0-7506-4282-3") . 
  12. ** ^  ** Goetsch, David L. (2005). [ _Technical Drawing_ ](https://books.google.com/books?id=eMqVygLDSa0C&pg=PA577) . Cengage Learning. [ ISBN ](/wiki/ISBN_\(identifier\) "ISBN \(identifier\)") [ 1-4018-5760-4  ](/wiki/Special:BookSources/1-4018-5760-4 "Special:BookSources/1-4018-5760-4") . 
  13. ^  _**a** _ _**b** _ _**c** _ _**d** _ _**e** _ _**f** _ _**g** _ _**h** _ [ "13.1: The motion of a spring-mass system" ](https://phys.libretexts.org/Bookshelves/University_Physics/Book%3A_Introductory_Physics_-_Building_Models_to_Describe_Our_World_\(Martin_Neary_Rinaldo_and_Woodman\)/13%3A_Simple_Harmonic_Motion/13.01%3A_The_motion_of_a_spring-mass_system) . _Physics LibreTexts_ . 17 September 2019  . Retrieved  19 April  2021  . 
  14. ** ^  ** [ "Harmonic motion" ](http://labman.phys.utk.edu/phys221core/modules/m11/harmonic_motion.html) . _labman.phys.utk.edu_ . Retrieved  19 April  2021  . 
  15. ** ^  ** [ "simple harmonic motion | Formula, Examples, & Facts" ](https://www.britannica.com/science/simple-harmonic-motion) . _Encyclopedia Britannica_ . Retrieved  19 April  2021  . 
  16. ** ^  ** [ "Compression Springs" ](https://www.coilspringsdirect.com/store/entex-compression-springs) . _Coil Springs Direct_ .