On toroidal cores: AL = microHenries/Turn or microHenries/Turn^2 ?

I am shopping for toroidal transformer cores.

Maybe I will buy a ferrite ring made out of this material:
http://www.mag-inc.com/home/Advanced-Search-Results?pn=zp48613tc

AL
= microHenries/Turn
or
=microHenries/Turn2
?

How do I convert between the to? What is their relationship?
Sometimes AL is given in uH/Turn, sometimes in uH/Turn2.

I know that it is a dumb question to ask for an engineering student who took a lot of maths,
but I am abit confused.
Thank you.

Inductance depends on turns-squared, so its uH/turn^2

The fact that manufacturer's datasheets get it wrong shouldn't be too suprising given things like "mhz" for "MHz", "N/m" for torque, etc etc.

Wikipedia and other sites will cover the basics of inductance of a solenoid or toroidal coil.

Oh yes, ferrite properties vary with temperature, you may want a gapped core if a stable value of inductance is needed. A gap tends to dominate the reluctance of the magnetic circuit and make it less dependent on the ferrite properties. Gapped inductors also can store more energy before saturation too.

Thank you.