Vol. I - DC, Physics of Conductors and Insulators, Introduction: In the first "Review" item, in the phrase "in that materials atoms" there should be an apostrophe before the "s" in "materials".

 

See: http://www.allaboutcircuits.com/vol_1/chpt_12/1.html

Yes, it should be: "in that material's atoms" since the word "material's" is possessive.

Thanks.

Dave