[USMA:44462] Strange SI units

[ezra . steinberg]

Just came across this article: 

http://ptonline.aip.org/journals/doc/PHTOAD-ft/vol_62/iss_4/25_1.shtml 

but was flummoxed by this part: 

$30/kA·m 

What the heck is kA·m and why do they use it? 

Ezra