おそらく、ディレクトリではなく HTML ファイルをインポートすると役立つ場合があります。
<link rel="import" href="bower_components/paper-tabs/paper-tabs.html">
その後の依存関係が解決されない可能性は、サーバーのルートの場所です。bower_components と同じディレクトリ レベルからサービスを提供している場合、上記の HTML インポートを同じレベルに挿入すると機能するはずです。
参考までに、依存関係のウォーターフォールは次のようになります。
$ bower install Polymer/paper-tabs
bower cached git://github.com/Polymer/paper-tabs.git#0.4.2
bower validate 0.4.2 against git://github.com/Polymer/paper-tabs.git#*
bower cached git://github.com/Polymer/core-selector.git#0.4.2
bower validate 0.4.2 against git://github.com/Polymer/core-selector.git#^0.4.0
bower cached git://github.com/Polymer/core-icons.git#0.4.2
bower validate 0.4.2 against git://github.com/Polymer/core-icons.git#^0.4.0
bower cached git://github.com/Polymer/core-toolbar.git#0.4.2
bower validate 0.4.2 against git://github.com/Polymer/core-toolbar.git#^0.4.0
bower cached git://github.com/Polymer/font-roboto.git#0.4.2
bower validate 0.4.2 against git://github.com/Polymer/font-roboto.git#^0.4.0
bower cached git://github.com/Polymer/paper-icon-button.git#0.4.2
bower validate 0.4.2 against git://github.com/Polymer/paper-icon-button.git#^0.4.0
bower cached git://github.com/Polymer/paper-ripple.git#0.4.2
bower validate 0.4.2 against git://github.com/Polymer/paper-ripple.git#^0.4.0
bower cached git://github.com/Polymer/polymer.git#0.4.2
bower validate 0.4.2 against git://github.com/Polymer/polymer.git#^0.4.0
bower cached git://github.com/Polymer/core-selection.git#0.4.2
bower validate 0.4.2 against git://github.com/Polymer/core-selection.git#^0.4.0
bower cached git://github.com/Polymer/core-icon.git#0.4.2
bower validate 0.4.2 against git://github.com/Polymer/core-icon.git#^0.4.0
bower cached git://github.com/Polymer/core-iconset-svg.git#0.4.2
bower validate 0.4.2 against git://github.com/Polymer/core-iconset-svg.git#^0.4.0
bower cached git://github.com/Polymer/core-icon-button.git#0.4.2
bower validate 0.4.2 against git://github.com/Polymer/core-icon-button.git#^0.4.0
bower cached git://github.com/Polymer/core-media-query.git#0.4.2
bower validate 0.4.2 against git://github.com/Polymer/core-media-query.git#^0.4.0
bower cached git://github.com/Polymer/paper-button.git#0.4.2
bower validate 0.4.2 against git://github.com/Polymer/paper-button.git#^0.4.0
bower cached git://github.com/Polymer/core-iconset.git#0.4.2
bower validate 0.4.2 against git://github.com/Polymer/core-iconset.git#^0.4.0
bower cached git://github.com/Polymer/paper-focusable.git#0.4.2
bower validate 0.4.2 against git://github.com/Polymer/paper-focusable.git#^0.4.0
bower cached git://github.com/Polymer/paper-shadow.git#0.4.2
bower validate 0.4.2 against git://github.com/Polymer/paper-shadow.git#^0.4.0
bower cached git://github.com/Polymer/core-component-page.git#0.4.2
bower validate 0.4.2 against git://github.com/Polymer/core-component-page.git#^0.4.0
bower cached git://github.com/Polymer/platform.git#0.4.2
bower validate 0.4.2 against git://github.com/Polymer/platform.git#^0.4.0
bower cached git://github.com/Polymer/core-meta.git#0.4.2
bower validate 0.4.2 against git://github.com/Polymer/core-meta.git#^0.4.0
bower install paper-tabs#0.4.2
bower install core-selector#0.4.2
bower install core-icons#0.4.2
bower install core-toolbar#0.4.2
bower install paper-ripple#0.4.2
bower install font-roboto#0.4.2
bower install paper-icon-button#0.4.2
bower install core-selection#0.4.2
bower install core-iconset-svg#0.4.2
bower install core-icon#0.4.2
bower install core-media-query#0.4.2
bower install core-icon-button#0.4.2
bower install paper-button#0.4.2
bower install polymer#0.4.2
bower install core-iconset#0.4.2
bower install paper-focusable#0.4.2
bower install paper-shadow#0.4.2
bower install core-component-page#0.4.2
bower install platform#0.4.2
bower install core-meta#0.4.2
paper-tabs#0.4.2 bower_components/paper-tabs
├── core-icons#0.4.2
├── core-selector#0.4.2
├── core-toolbar#0.4.2
├── font-roboto#0.4.2
├── paper-icon-button#0.4.2
└── paper-ripple#0.4.2
core-selector#0.4.2 bower_components/core-selector
├── core-selection#0.4.2
└── polymer#0.4.2
core-icons#0.4.2 bower_components/core-icons
├── core-icon#0.4.2
├── core-iconset-svg#0.4.2
└── polymer#0.4.2
core-toolbar#0.4.2 bower_components/core-toolbar
├── core-icon-button#0.4.2
└── core-media-query#0.4.2
paper-ripple#0.4.2 bower_components/paper-ripple
├── core-icon#0.4.2
├── core-icons#0.4.2
└── font-roboto#0.4.2
font-roboto#0.4.2 bower_components/font-roboto
paper-icon-button#0.4.2 bower_components/paper-icon-button
├── core-selector#0.4.2
├── paper-button#0.4.2
└── polymer#0.4.2
core-selection#0.4.2 bower_components/core-selection
└── polymer#0.4.2
core-iconset-svg#0.4.2 bower_components/core-iconset-svg
├── core-iconset#0.4.2
└── polymer#0.4.2
core-icon#0.4.2 bower_components/core-icon
├── core-icons#0.4.2
└── core-iconset#0.4.2
core-media-query#0.4.2 bower_components/core-media-query
└── polymer#0.4.2
core-icon-button#0.4.2 bower_components/core-icon-button
└── core-icons#0.4.2
paper-button#0.4.2 bower_components/paper-button
├── core-icon#0.4.2
├── paper-focusable#0.4.2
├── paper-ripple#0.4.2
├── paper-shadow#0.4.2
└── polymer#0.4.2
polymer#0.4.2 bower_components/polymer
├── core-component-page#0.4.2
└── platform#0.4.2
core-iconset#0.4.2 bower_components/core-iconset
├── core-icon#0.4.2
├── core-meta#0.4.2
└── polymer#0.4.2
paper-focusable#0.4.2 bower_components/paper-focusable
└── polymer#0.4.2
paper-shadow#0.4.2 bower_components/paper-shadow
└── polymer#0.4.2
core-component-page#0.4.2 bower_components/core-component-page
├── platform#0.4.2
└── polymer#0.4.2
platform#0.4.2 bower_components/platform
core-meta#0.4.2 bower_components/core-meta
└── polymer#0.4.2
paper-tabs ディレクトリはこれらのファイルを生成します (ディレクトリに追加されたバージョン番号はありません):
README.md demo.html metadata.html paper-tab.html paper-tabs.html
bower.json index.html paper-tab.css paper-tabs.css