URL
Title
Id
http://digfir-published.macmillanusa.com/cogtk/inversion effect.html
Chapter
1
.
Inversion Effect
50e76a1fb11c0fa677000000
http://digfir-published.macmillanusa.com/cogtk/inversion effect_dlap.xml
DLAP questions
50e76a1fb11c0fa677000000