<h2>
<?php $ariane_params = array("morceau" => $this->out["morceau"]["id"]); ?>
-<?php if($this->out["album"]) : $ariane_params["album"] = $this->out["album"]["id"]; ?>
+<?php if(isset($this->out["album"]) && $this->out["album"]) : $ariane_params["album"] = $this->out["album"]["id"]; ?>
<a href="<?php echo $this->url("sources/album/view", $ariane_params) ?>">
<?php echo $this->out["album"]["titre"] ?>
</a>