Ambien Information from Sanofi-Aventis
The manufacturer presents its introduction and overview of Ambien.
MedlinePlus Drug Information: Zolpidem (marketed as Ambien)
The US Library of Congress provides for a detailed information on Ambien.
MedlinePlus Medical Encyclopedia: Sleeping Difficulty
Insomnia information from the U.S. National Library of Medicine and the National Institutes of Health.