[pm#graph1_on_description_container
     [any pm#description_container (^$(no inheritance)$^),
          pm#physical_support: a pm#physical_entity,
          pm#descr_container of: a pm#description,
          pm#result of: a #writing,
          may have for pm#url: a pm#URL,
          may have for pm#relation_from_description_content/medium/container (^$(explore)$^): a pm#thing]
];


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