diff --git a/tests/test_jstor.py b/tests/test_jstor.py
index 551715e..0ee0d76 100644
--- a/tests/test_jstor.py
+++ b/tests/test_jstor.py
@@ -8,13 +8,13 @@ class JSTORTestCase(unittest.TestCase):
         file_handler = open("tests/samples/jstor/231a515256115368c142f528cee7f727.pdf", "rb")
         content = file_handler.read()
         file_handler.close()
-        self.assertIn("\n18 0 obj \n", content)
+        self.assertIn(b"\n18 0 obj \n", content)
 
         # this section will later be manipulated
-        self.assertIn("\n19 0 obj \n", content)
+        self.assertIn(b"\n19 0 obj \n", content)
 
         output = pdfparanoia.plugins.JSTOR.scrub(content)
 
         # FlateDecode should be replaced with a decompressed section
-        self.assertIn("\n19 0 obj\n<</Length 2862>>stream", output)
+        self.assertIn(b"\n19 0 obj\n<</Length 2862>>stream", output)