Umlaut URL parameters
Umlaut has a few custom URL parameters (can also be sent in a POST request) to control Umlaut behavior. All start with the prefix "umlaut.". These are generally added onto an OpenURL GET request.
Specify an already created OpenURL request to act upon. Without this, Umlaut will still try to connect to an already created request *within the same session* based on a cache of OpenURLs seen in that session. But this process is not perfect. With umlaut.request_id, you can assure you are operating on the same request, and even if the client does not have cookies or a session.
Specify an Umlaut Referent object to re-use. Umlaut referent object represents a particular citation. Unlike umlaut.request_id, won't re-use an entire request (with responses and state), but only the specified citation.
Set to "false" to override umlaut's configuration for conditionally skipping the the resolve menu and going straight to content. umlaut.skip_resolve_menu=false forces display of full resolve menu.
Generally used for API requests, value can be "xml", "json", or "jsonp". In case of jsonp, umlaut.jsonp=jsFunctionName can be used to determine the js function name that will be generated with the [jsonp output|http://ajaxian.com/archives/jsonp-json-with-padding]