References

1. Martin Gardner, "Jumping pencil," Phys. Teach. 37, 178 (March 1999). first citation in article
   
2. A commercial version of this apparatus is available from Arbor Scientific (http://www.arborsci.com). An additional demonstration that can be done with this apparatus is pictured in the Arbor catalog. first citation in article
   
3. Another demonstration using similar apparatus is described in James P. Louviere, "The inscrutable, open-ended toy balloon," Phys. Teach. 27, 195 (Feb. 1989). first citation in article
   
4. Most PET water and soft drink bottles available in the U.S. are too thin-walled and will tend to collapse. Some juice bottles work better. first citation in article