// in the module initialization program
class XxiiModule extends CWebModule
{
    ...
    // getAssetsUrl()
    //    return the URL for this module's assets, performing the publish operation
    //    the first time, and caching the result for subsequent use.
    private $_assetsUrl;
 
    public function getAssetsUrl()
    {
        if ($this->_assetsUrl === null)
            $this->_assetsUrl = Yii::app()->getAssetManager()->publish(
                Yii::getPathOfAlias('xxii.assets') );
        return $this->_assetsUrl;
    }
    ....
 
// xxii/views/layouts/main.php
 
   <link rel="stylesheet"
         type="text/css"
         href="<?php echo $this->module->assetsUrl; ?>/css/main.css"/>
   ...
   <div id="logo">
   <?php echo CHtml::link(
                 CHtml::image($this->module->assetsUrl.'/images/logo.png'),
                 array('/xxii')); ?>
   </div>