A horn bow with a sinew backing or if the horn has a piece or pieces of wood glued to its back is a backed bow. Two gemsbok horns connected by a wood plug would be a self bow. Billeted staves such as those sold by Gary Davis or yew staves made by splicing two pieces of wood together would still be considered a self bow if no backing to added to the back of the wood. I think that further categories should be made for bows backed with sinew and hide glue to not compete against bows backed with bamboo or hickory or other wood if epoxy is necessary for the bow to function or if a planer or other piece of cabinetry machinery is necessary to build it. A hand made Japanese yumi would be an example of a wood and bamboo laminated bow not using epoxy or needing machine made wood lams.
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