Asian Rainforest: Siamang - Video of a brachiating and walking siamang from the Oakland (CA) Zoo's website.
Gibbon Conservation Center - Santa Clarita, California. Established in 1976 for the study, propagation, conservation and betterment of the highly endangered small ape, the gibbon. Information about the center, voluteering, and donations.
Gibbon Research Lab - Natural history, systematics, photos and sounds of all gibbon species, publications, and links.
Kalaweit - A French non-profit organisation for gibbon and siamang conservation. Projects in Borneo and Sumatra, funding and donations.
Silvery Gibbon Project - Hylobates moloch is a critically endangered species unique to Java in South-East Asia. Includes vocalizations, information on threatened habitat, and details of conservation efforts.
The Singing Apes - An article by Kashmira Kakati studying the world of the hoolock gibbons in the Borajan reserve forest in Assam.