1: ...
 [by parsing <frames.n3>]

2: <http://notes.restdesc.org/2013/frames/Frame1> a :VideoFrame .
 [by erasure from step 1]

3: ...
 [by parsing <frames.n3>]

4: @forAll :x0 . { :x0 a f:VideoFrame . } <http://www.w3.org/2000/10/swap/log#implies> {:x0 a f:Image . } .
 [by erasure from step 3]

5: <http://notes.restdesc.org/2013/frames/Frame1> a :Image .
 [by rule from step 4 applied to steps [2]
  with bindings {'x0': u'<http://notes.restdesc.org/2013/frames/Frame1>'}]

6: ...
 [by parsing <query.n3>]

7: @forAll :x0 . { :x0 a f:Image . } <http://www.w3.org/2000/10/swap/log#implies> {:x0 a f:Image . } .
 [by erasure from step 6]

8: <http://notes.restdesc.org/2013/frames/Frame1> a :Image .
 [by rule from step 7 applied to steps [5]
  with bindings {'x0': u'<http://notes.restdesc.org/2013/frames/Frame1>'}]

9: <http://notes.restdesc.org/2013/frames/Frame1> a :Image .
 [by conjoining steps [8]]

     @prefix : <http://notes.restdesc.org/2013/frames/frames#> .
    
    <http://notes.restdesc.org/2013/frames/Frame1>     a :Image .