Base a pagination.PageResult on gophercloud.Result.
diff --git a/openstack/objectstorage/v1/containers/results.go b/openstack/objectstorage/v1/containers/results.go
index 3a6d3be..ec3c1e0 100644
--- a/openstack/objectstorage/v1/containers/results.go
+++ b/openstack/objectstorage/v1/containers/results.go
@@ -67,7 +67,7 @@
 // ExtractNames is a function that takes a ListResult and returns the containers' names.
 func ExtractNames(page pagination.Page) ([]string, error) {
 	casted := page.(ContainerPage)
-	ct := casted.Header.Get("Content-Type")
+	ct := casted.Headers.Get("Content-Type")
 
 	switch {
 	case strings.HasPrefix(ct, "application/json"):