diff --git a/book.php b/book.php
--- a/book.php
+++ b/book.php
@@ -1,5 +1,7 @@
 <?php
 
+use EasyRdf\Graph;
+
 class Book {
     /**
      * OCLC number
@@ -10,7 +12,7 @@
         $oclc = (string)(int)$this->OCLC;
 
         $url = 'http://www.worldcat.org/oclc/' . $oclc;
-        $rdf = new EasyRdf_Graph($url . '.rdf');
+        $rdf = new Graph($url . '.rdf');
         $rdf->load();
         $resources = $rdf->resources();
         $book = $resources[$url];
diff --git a/composer.json b/composer.json
--- a/composer.json
+++ b/composer.json
@@ -20,7 +20,7 @@
     ],
     "require": {
         "php": ">=5.4",
-        "easyrdf/easyrdf": "*"
+        "easyrdf/easyrdf": "~1.1.1"
     },
     "support": {
         "issues": "http://devcentral.nasqueron.org/tag/nasqueron_tools/",