. "efforts to preserve the art" . "add oil machine" . . . "coordinated preservation efforts" . "Art of the Umbrella Movement" . "Lennon Wall" . "physical and digital preservation" . "artworks of the Umbrella Movement" . "Art_of_the_Umbrella_Movement#Preservation" . "arts of the Umbrella Movement" . . "Stand By You: Add Oil Machine" . "Art of the Umbrella Movement" . . . "Art" . . . "widely reposted image" .