diff --git a/specs/data/box-external-resources/box-external-resources.mtl b/specs/data/box-external-resources/box-external-resources.mtl
new file mode 100644
index 0000000..2e2d3a5
--- /dev/null
+++ b/specs/data/box-external-resources/box-external-resources.mtl
@@ -0,0 +1,13 @@
+# Blender MTL File: 'box.blend'
+# Material Count: 1
+
+newmtl MaterialTextured
+Ns 96.078431
+Ka 0.000000 0.000000 0.000000
+Kd 0.640000 0.640000 0.640000
+Ks 0.500000 0.500000 0.500000
+Ke 0.000000 0.000000 0.000000
+Ni 1.000000
+d 1.000000
+illum 2
+map_Kd ../box-textured/cesium.png
diff --git a/specs/data/box-external-resources/box-external-resources.obj b/specs/data/box-external-resources/box-external-resources.obj
new file mode 100644
index 0000000..8786fa7
--- /dev/null
+++ b/specs/data/box-external-resources/box-external-resources.obj
@@ -0,0 +1,46 @@
+# Blender v2.78 (sub 0) OBJ File: 'box-multiple-materials.blend'
+# www.blender.org
+mtllib box-external-resources.mtl
+mtllib ../box/box.mtl
+v -1.000000 -1.000000 1.000000
+v -1.000000 1.000000 1.000000
+v -1.000000 -1.000000 -1.000000
+v -1.000000 1.000000 -1.000000
+v 1.000000 -1.000000 1.000000
+v 1.000000 1.000000 1.000000
+v 1.000000 -1.000000 -1.000000
+v 1.000000 1.000000 -1.000000
+vt 0.0000 0.0000
+vt 1.0000 0.0000
+vt 1.0000 1.0000
+vt 0.0000 1.0000
+vt 0.0000 0.0000
+vt 1.0000 0.0000
+vt 1.0000 1.0000
+vt 0.0000 1.0000
+vt 0.0000 0.0000
+vt 1.0000 0.0000
+vt 1.0000 1.0000
+vt 0.0000 1.0000
+vt 0.0000 0.0000
+vt 1.0000 0.0000
+vt 1.0000 1.0000
+vt 0.0000 1.0000
+vt 1.0000 1.0000
+vt 0.0000 1.0000
+vt 0.0000 0.0000
+vt 1.0000 0.0000
+vn 0.0000 -1.0000 0.0000
+vn 0.0000 1.0000 0.0000
+vn -1.0000 0.0000 0.0000
+vn 1.0000 0.0000 0.0000
+vn 0.0000 0.0000 -1.0000
+vn 0.0000 0.0000 1.0000
+usemtl MaterialTextured
+f 3/1/1 7/2/1 5/3/1 1/4/1
+f 1/9/3 2/10/3 4/11/3 3/12/3
+f 3/1/5 4/6/5 8/17/5 7/18/5
+usemtl Material
+f 8/5/2 4/6/2 2/7/2 6/8/2
+f 7/13/4 8/14/4 6/15/4 5/16/4
+f 5/19/6 6/20/6 2/7/6 1/4/6