http://wifo5-40.informatik.uni-mannheim.de:8890/sparql?query=DESCRIBE%20%3Chttp%3A%2F%2Fwebisa.webdatacommons.org%2F46887598%3E&format=application%2Fatom%2Bxml2024-03-28T17:56:53.174293ZOData Service and Descriptor Documenthttp://webisa.webdatacommons.org/468875982024-03-28T17:56:53.174293ZSuch a shelf is optional; one alternative is a tilted tray for holding papers or an iPad.