' ELSE ''END+CASE WHEN LinkAmazon IS NULL OR LinkAmazon='' THEN '' ELSE '' END + CASE WHEN LinkIbook IS NULL OR LinkIbook='' THEN '' ELSE '' END + CASE WHEN LinkOnline IS NULL OR LinkOnline='' THEN '' ELSE '' END + CASE WHEN SingleChapters IS NULL OR SingleChapters='' THEN '' ELSE '' END + CASE WHEN LinkLibraryColl IS NULL OR LinkLibraryColl='' THEN '' ELSE '' END + CASE WHEN LinkPersonalColl IS NULL OR LinkPersonalColl='' THEN '' ELSE '' END + '