With 650 million persons with disabilities worldwide, the new guide -- "Convention on the Rights of Persons with Disabilities and its Optional Protocol" -- seeks to help address "the marginalization that so many have suffered worldwide," the U.N. Office of the High Commissioner for Human Rights said in a news release.

"I hope that the handbook, in addition to raising awareness, will foster the speedy ratification of the convention ... to end the protection vacuum that has ... affected persons with disabilities," said Louise Arbour, U.N. human rights high commissioner.

The English version of the handbook was launched Monday before legislators attending the a meeting of the Inter-Parliamentary Union Assembly in in Geneva. The IPU has permanent observer status at the United Nations.